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  • 1. Adelman, S.J.
    et al.
    Gulliver, A.F.
    Kochukhov, Oleg
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Astronomy and Space Physics. Department of Physics and Astronomy, Observational Astronomy.
    Ryabchikova, T.
    The variability of the HgII lambda 3984 line of the mercury-manganese star alpha Andromedae2002In: Astrophysical Journal, ISSN 0004-637X, Vol. 575, p. 449-Article in journal (Refereed)
  • 2.
    Airapetian, Vladimir S.
    et al.
    Amer Univ, 4400 Massachusetts Ave NW, Washington, DC 20016 USA.;NASA, GSFC, SEEC, Greenbelt, MD 20771 USA..
    Jin, Meng
    SETI, 189 N Bernardo Ave 200, Mountain View, CA 94043 USA..
    Luftinger, Theresa
    ESA, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Boro Saikia, Sudeshna
    Univ Vienna, Dept Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Guedel, Manuel
    Univ Vienna, Dept Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria..
    Van Der Holst, Bart
    Univ Michigan, Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA..
    Manchester, W.
    Univ Michigan, Atmospher Ocean & Space Sci, Ann Arbor, MI 48109 USA..
    One Year in the Life of Young Suns: Data-constrained Corona-wind Model of κ1 Ceti2021In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 916, no 2, article id 96Article in journal (Refereed)
    Abstract [en]

    The young magnetically active solar-like stars are efficient generators of ionizing radiation in the form of X-ray and extreme-UV (EUV) flux, stellar wind, and eruptive events. These outputs are the critical factors affecting atmospheric escape and chemistry of (exo)planets around active stars. While X-ray fluxes and surface magnetic fields can be derived from observations, the EUV emission, and wind mass fluxes, coronal mass ejections and associated stellar energetic particle events cannot be directly observed. Here, we present the results of a three-dimensional magnetohydrodynamic (MHD) model with inputs constrained by spectropolarimetric data, Hubble Space Telescope/STIS far-UV and X-ray data, and stellar magnetic maps reconstructed at two epochs separated by 11 months. The simulations show that over the course of the year the global stellar corona had undergone a drastic transition from a simple dipole-like to a tilted dipole with multipole field components and thus provided favorable conditions for corotating interaction regions (CIRs) that drive strong shocks. The dynamic pressures exerted by CIRs are 1300 times larger than those observed from the Sun and can contribute to the atmospheric erosion of early Venus, Earth, Mars, and young Earth-like exoplanets. Our data-constrained MHD model provides the framework to model coronal environments of G-M planet-hosting dwarfs. The model outputs can serve as a realistic input for exoplanetary atmospheric models to evaluate the impact of stellar coronal emission, stellar winds, and CIRs on their atmospheric escape and chemistry that can be tested in the upcoming James Webb Space Telescope and ground-based observations.

  • 3. Alecian, E.
    et al.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Neiner, C.
    Wade, G. A.
    de Batz, B.
    Henrichs, H.
    Grunhut, J. H.
    Bouret, J. -C
    Briquet, M.
    Gagne, M.
    Naze, Y.
    Oksala, M. E.
    Rivinius, T.
    Townsend, R. H. D.
    Walborn, N. R.
    Weiss, W.
    First HARPSpol discoveries of magnetic fields in massive stars2011In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 536, p. L6-Article in journal (Refereed)
    Abstract [en]

    In the framework of the Magnetism in Massive Stars (MiMeS) project, a HARPSpol Large Program at the 3.6m-ESO telescope has recently started to collect high-resolution spectropolarimetric data of a large number of Southern massive OB stars in the field of the Galaxy and in many young clusters and associations. We report on the first discoveries of magnetic fields in two massive stars with HARPSpol - HD 130807 and HD 122451, and confirm the presence of a magnetic field at the surface of HD 105382 that was previously observed with a low spectral resolution device. The longitudinal magnetic field measurements strongly vary for HD 130807 from similar to-100 G to similar to 700 G. Those of HD 122451 and HD 105382 are less variable with values ranging from similar to-40 to -80 G, and from similar to-300 to -600 G, respectively. The discovery and confirmation of three new magnetic massive stars, including at least two He-weak stars, is an important contribution to one of MiMeS objectives: the understanding of the origin of magnetic fields in massive stars and their impact on stellar structure and evolution.

  • 4. Alecian, E.
    et al.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Petit, V.
    Grunhut, J.
    Landstreet, J.
    Oksala, M. E.
    Wade, G. A.
    Hussain, G.
    Neiner, C.
    Bohlender, D.
    Discovery of new magnetic early-B stars within the MiMeS HARPSpol survey2014In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 567, p. A28-Article in journal (Refereed)
    Abstract [en]

    Context. The Magnetism in Massive Stars (MiMeS) project aims at understanding the origin of the magnetic fields in massive stars as well as their impact on stellar internal structure, evolution, and circumstellar environment. Aims. One of the objectives of the MiMeS project is to provide stringent observational constraints on the magnetic fields of massive stars; however, identification of magnetic massive stars is challenging, as only a few percent of high-mass stars host strong fields detectable with the current instrumentation. Hence, one of the first objectives of the MiMeS project was to search for magnetic objects among a large sample of massive stars, and to build a sub-sample for in-depth follow-up studies required to test the models and theories of fossil field origins, magnetic wind confinement and magnetospheric properties, and magnetic star evolution. Methods. We obtained high-resolution spectropolarimetric observations of a large number of OB stars thanks to three large programs (LP) of observations that have been allocated on the high-resolution spectropolarimeters ESPaDOnS, Narval, and the polarimetric module HARPSpol of the HARPS spectrograph. We report here on the methods and first analysis of the HARPSpol magnetic detections. We identified the magnetic stars using a multi-line analysis technique. Then, when possible, we monitored the new discoveries to derive their rotation periods, which are critical for follow-up and magnetic mapping studies. We also performed a first-look analysis of their spectra and identified obvious spectral anomalies (e. g., surface abundance peculiarities, Ha emission), which are also of interest for future studies. Results. In this paper, we focus on eight of the 11 stars in which we discovered or confirmed a magnetic field from the HARPSpol LP sample (the remaining three were published in a previous paper). Seven of the fields were detected in early-type Bp stars, while the last field was detected in the Ap companion of a normal early B-type star. We report obvious spectral and multiplicity properties, as well as our measurements of their longitudinal field strengths, and their rotation periods when we are able to derive them. We also discuss the presence or absence of Ha emission with respect to the theory of centrifugally-supported magnetospheres.

  • 5. Alecian, E.
    et al.
    Neiner, C.
    Mathis, S.
    Catala, C.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Landstreet, J.
    The dramatic change of the fossil magnetic field of HD 190073: Evidence of the birth of the convective core in a Herbig star?2013In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 549, p. L8-Article in journal (Refereed)
    Abstract [en]

    In the context of the ESPaDOnS and Narval spectropolarimetric surveys of Herbig Ae/Be stars, we discovered and then monitored the magnetic field of HD 190073 over more than four years, from 2004 to 2009. Our observations all displayed similar Zeeman signatures in the Stokes V spectra, indicating that HD 190073 hosted an aligned dipole, stable over many years, consistent with a fossil origin. We obtained new observations of the star in 2011 and 2012 and detected clear variations of the Zeeman signature on timescales of days to weeks, indicating that the configuration of its field has changed between 2009 and 2011. Such a sudden change of external structure of a fossil field has never previously been observed in any intermediate or high-mass star. HD 190073 is an almost entirely radiative pre-main sequence star, probably hosting a growing convective core. We propose that this dramatic change is the result of the interaction between the fossil field and the ignition of a dynamo field generated in the newly-born convective core.

  • 6. Alentiev, D.
    et al.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Ryabchikova, T.
    Cunha, M.
    Tsymbal, V.
    Weiss, W.
    Discovery of the longest period rapidly oscillating Ap star HD1777652012In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 421, no 1, p. L82-L86Article in journal (Refereed)
    Abstract [en]

    We present the discovery of a long-period, rapidly oscillating Ap (roAp) star, HD177765. Using high-resolution time-series observations obtained with the Ultraviolet and Visual Echelle Spectrograph at the European Southern Observatory Very Large Telescope, we found radial velocity variations with amplitudes 7-150 ms(-1) and a period of 23.6 min, exceeding that of any previously known roAp star. The largest pulsation amplitudes are observed for Eu III, Ce III and for the narrow core of H alpha. We derived the atmospheric parameters and chemical composition of HD177765, showing this star to be similar to other long-period roAp stars. Comparison with theoretical pulsational models indicates an advanced evolutionary state for HD177765. Abundance analyses of this and other roAp stars suggest a systematic variation with age of the rare-earth line anomalies seen in cool Ap stars.

  • 7.
    Alvarado-Gomez, J. D.
    et al.
    European So Observ, D-85748 Garching, Germany.;Univ Munich, Univ Sternwarte Munchen, D-81679 Munich, Germany..
    Hussain, G. A. J.
    European So Observ, D-85748 Garching, Germany.;Univ Toulouse, UPS OMP, Inst Rech Astrophys & Planetol, F-31400 Toulouse, France..
    Grunhut, J.
    European So Observ, D-85748 Garching, Germany..
    Fares, R.
    INAF Osservatorio Astrofis Catania, I-95123 Catania, Italy..
    Donati, J. -F
    Alecian, E.
    UJF Grenoble 1, CNRS, INSU, IPAG,UMR 5274, Grenoble, France.;Univ Paris Diderot, UPMC, CNRS, LESIA,Observ Paris,UMR 8109, F-92190 Meudon, France..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Oksala, M.
    Univ Paris Diderot, UPMC, CNRS, LESIA,Observ Paris,UMR 8109, F-92190 Meudon, France..
    Morin, J.
    CNRS, UMR 5299, LUPM, F-34095 Montpellier 05, France.;Univ Montpellier, F-34095 Montpellier 05, France..
    Redfield, S.
    Wesleyan Univ, Dept Astron, Van Vleck Observ, Middletown, CT 06459 USA..
    Cohen, O.
    Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA..
    Drake, J. J.
    Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA..
    Jardine, M.
    Univ St Andrews, Sch Phys & Astron, SUPA, St Andrews KY16 9SS, Fife, Scotland..
    Matt, S.
    Univ Exeter, Dept Phys & Astron, Exeter EX4 4SB, Devon, England..
    Petit, P.
    Univ Toulouse, UPS OMP, Inst Rech Astrophys & Planetol, F-31400 Toulouse, France.;CNRS, Inst Rech Astrophys & Planetol, F-31400 Toulouse, France..
    Walter, F. M.
    SUNY Stony Brook, Dept Phys & Astron, Stony Brook, NY 11794 USA..
    Activity and magnetic field structure of the Sun-like planet-hosting star HD 12372015In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 582, article id A38Article in journal (Refereed)
    Abstract [en]

    We analyse the magnetic activity characteristics of the planet-hosting Sun-like star, HD 1237, using HARPS spectro-polarimetric time-series data. We find evidence of rotational modulation of the magnetic longitudinal field measurements that is consistent with our ZDI analysis with a period of 7 days. We investigate the effect of customising the LSD mask to the line depths of the observed spectrum and find that it has a minimal effect on the shape of the extracted Stokes V profile but does result in a small increase in the S/N (similar to 7%). We find that using a Milne-Eddington solution to describe the local line profile provides a better fit to the LSD profiles in this slowly rotating star, which also affects the recovered ZDI field distribution. We also introduce a fit-stopping criterion based on the information content (entropy) of the ZDI map solution set. The recovered magnetic field maps show a strong (+90 G) ring-like azimuthal field distribution and a complex radial field dominating at mid latitudes (similar to 45 degrees). Similar magnetic field maps are recovered from data acquired five months apart. Future work will investigate how this surface magnetic field distribution affeccts the coronal magnetic field and extended environment around this planet-hosting star.

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  • 8.
    Alvarado-Gomez, Julian D.
    et al.
    Leibniz Inst Astrophys Potsdam, Sternwarte 16, D-14482 Potsdam, Germany..
    Cohen, Ofer
    Univ Massachusetts, Dept Phys & Appl Phys, 600 Suffolk St, Lowell, MA 01854 USA..
    Drake, Jeremy J.
    Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA..
    Fraschetti, Federico
    Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA.;Univ Arizona, Dept Planetary Sci, Lunar & Planetary Lab, Tucson, AZ 85721 USA..
    Poppenhaeger, Katja
    Leibniz Inst Astrophys Potsdam, Sternwarte 16, D-14482 Potsdam, Germany.;Univ Potsdam, Inst Phys & Astron, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany..
    Garraffo, Cecilia
    Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA..
    Chebly, Judy
    Leibniz Inst Astrophys Potsdam, Sternwarte 16, D-14482 Potsdam, Germany.;Univ Potsdam, Inst Phys & Astron, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany..
    Ilin, Ekaterina
    Leibniz Inst Astrophys Potsdam, Sternwarte 16, D-14482 Potsdam, Germany.;Univ Potsdam, Inst Phys & Astron, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany..
    Harbach, Laura
    Imperial Coll London, Dept Phys, Astrophys Grp, Prince Consort Rd, London SW7 2AZ, England..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Simulating the Space Weather in the AU Mic System: Stellar Winds and Extreme Coronal Mass Ejections2022In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 928, no 2, article id 147Article in journal (Refereed)
    Abstract [en]

    Two close-in planets have been recently found around the M-dwarf flare star AU Microscopii (AU Mic). These Neptune-sized planets (AU Mic b and c) seem to be located very close to the so-called "evaporation valley" in the exoplanet population, making this system an important target for studying atmospheric loss on exoplanets. This process, while mainly driven by high-energy stellar radiation, will be strongly mediated by the space environment surrounding the planets. Here we present an investigation of this last area, performing 3D numerical modeling of the quiescent stellar wind from AU Mic, as well as time-dependent simulations describing the evolution of a highly energetic coronal mass ejection (CME) event in this system. Observational constraints on the stellar magnetic field and properties of the eruption are incorporated in our models. We carry out qualitative and quantitative characterizations of the stellar wind, the emerging CMEs, as well as the expected steady and transient conditions along the orbit of both exoplanets. Our results predict extreme space weather for AU Mic and its planets. This includes sub-Alfvenic regions for the large majority of the exoplanet orbits, very high dynamic and magnetic pressure values in quiescence (varying within 10(2)-10(5) times the dynamic pressure experienced by Earth), and an even harsher environment during the passage of any escaping CME associated with the frequent flaring observed in AU Mic. These space weather conditions alone pose an immense challenge for the survival of exoplanetary atmospheres (if any) in this system.

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  • 9.
    Asensio Ramos, A.
    et al.
    Inst Astrofis Canarias, C Via Lactea S-N, Tenerife 38205, Spain.;Univ La Laguna, Dept Astrofis, Tenerife 38206, Spain..
    Diaz Baso, C. J.
    Stockholm Univ, Alballova Univ Ctr, Dept Astron, Inst Solar Phys, S-10691 Stockholm, Sweden..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Approximate Bayesian neural Doppler imaging2022In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 658, article id A162Article in journal (Refereed)
    Abstract [en]

    Aims. The non-uniform surface temperature distribution of rotating active stars is routinely mapped with the Doppler imaging technique. Inhomogeneities in the surface produce features in high-resolution spectroscopic observations that shift in wavelength because of the Doppler effect, depending on their position on the visible hemisphere. The inversion problem has been systematically solved using maximum a posteriori regularized methods assuming smoothness or maximum entropy. Our aim in this work is to solve the full Bayesian inference problem by providing access to the posterior distribution of the surface temperature in the star compatible with the observations. Methods. We use amortized neural posterior estimation to produce a model that approximates the high-dimensional posterior distribution for spectroscopic observations of selected spectral ranges sampled at arbitrary rotation phases. The posterior distribution is approximated with conditional normalizing flows, which are flexible, tractable, and easy-to-sample approximations to arbitrary distributions. When conditioned on the spectroscopic observations, these normalizing flows provide a very efficient way of obtaining samples from the posterior distribution. The conditioning on observations is achieved through the use of Transformer encoders, which can deal with arbitrary wavelength sampling and rotation phases. Results. Our model can produce thousands of posterior samples per second, each one accompanied by an estimation of the log-probability. Our exhaustive validation of the model for very high-signal-to-noise observations shows that it correctly approximates the posterior, albeit with some overestimation of the broadening. We apply the model to the moderately fast rotator II Peg, producing the first Bayesian map of its temperature inhomogenities. We conclude that conditional normalizing flows are a very promising tool for carrying out approximate Bayesian inference in more complex problems in stellar physics, such as constraining the magnetic properties using polarimetry.

  • 10. Bagnulo, S.
    et al.
    Fossati, L.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Landstreet, J. D.
    The importance of non-photon noise in stellar spectropolarimetry The spurious detection of a non-existing magnetic field in the AO supergiant HD 922072013In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 559, p. A103-Article in journal (Refereed)
    Abstract [en]

    Context. The low-resolution, Cassegrain mounted, FORS spectropolarimeter of the ESO Very Large Telescope is being extensively used for magnetic field surveys. Some of the new discoveries suggest that relatively strong magnetic fields may play an important role in numerous physical phenomena observed in the atmospheres as well as in the circumstellar environments of certain kinds of stars. Aims. We show in detail how small instabilities or data-reduction inaccuracies represent an alternative explanation for the origin of certain signals of circular polarisation published in recent years. Methods. With the help of analytical calculations we simulate the observation of a spectral line in spectropolarimetric mode, adding very small spurious wavelength shifts, which may mimic the effects of seeing variations, rapid variations of the stellar radial velocity, or instrument instabilities. As a case study, we then re-visit the FORS2 measurements that have been used to claim the discovery of a magnetic field in the A0 supergiant HD 92207. In addition, we present new observations of this star obtained with the HARPSpol instrument. Results. Both calibration and science data show compelling evidence that photon-noise is not the only source of error in magnetic field measurements, especially in sharp spectral lines. Non-photon noise may be kept under control by accurate data reduction and quality controls. Our re-analysis of FORS2 observations of HD 92207 shows no evidence of a magnetic field, and we are able to reproduce the previous FORS detection only by degrading the quality of our wavelength calibration. Our HARPSpol spectropolarimetric measurements show no evidence of a magnetic field at the level of 10 G. Conclusions. Our work contributes to a better understanding of the importance of accurate data treatment and instrument characterisation, and demonstrates that ultra-high signal-to-noise ratio measurements do not automatically translate into ultra-high accuracy.

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  • 11.
    Bagnulo, S.
    et al.
    Armagh Observ, Coll Hill, Armagh BT1 9DG, North Ireland..
    Fossati, L.
    Univ Bonn, Argelander Inst Astron, D-53121 Bonn, Germany..
    Landstreet, J. D.
    Armagh Observ, Coll Hill, Armagh BT1 9DG, North Ireland.;Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    The importance of non-photon noise in astronomical spectropolarimetry2015In: Polarimetry: From The Sun To Stars And Stellar Environments / [ed] Nagendra, KN Bagnulo, S Centeno, R Gonzalez, MJM, CAMBRIDGE UNIV PRESS , 2015, no 305, p. 181-185Conference paper (Refereed)
    Abstract [en]

    Stellar spectropolarimetry has become an extremely popular technique during the last decade or two, and has led to major advances in the studies of stellar magnetic fields. Many important discoveries have been made thanks to ultra-precise measurements of very small polarimetric signals, which require very stable instruments and special observing strategies. The so called beam-swapping technique is a well-known polarimetric technique capable of suppressing many spurious signals due to various instrumental effects. However, when one is interested in ultra-high signal-to-noise ratio measurements, observers start to hit various limitations introduced by the instrument, by the atmosphere, and even by the software for data-reduction. These limitations cannot be overcome by the observing strategies, and sources of errors other than photon-noise must be taken into account. Here we discuss the advantages of the beam-swapping technique, and the impact of small instrument and atmospheric instabilities, and how these issues offer an explanation for the origin of the apparently significant observed polarisation signals produced by effects other than those intrinsic to the observed target.

  • 12. Bagnulo, S.
    et al.
    Landstreet, J. D.
    Fossati, L.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Magnetic field measurements and their uncertainties: the FORS1 legacy2012In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 538, p. A129-Article in journal (Refereed)
    Abstract [en]

    Context. During the last decade, the FORS1 instrument of the ESO Very Large Telescope has been extensively used to study stellar magnetism. A number of interesting discoveries of magnetic fields in several classes of stars have been announced, many of which obtained at a similar to 3 sigma level; some of the discoveries are confirmed by measurements obtained with other instruments, some are not.

    Aims. We investigate the reasons for the discrepancies between the results obtained with FORS1 and those obtained with other instruments.

    Methods. Using the ESO FORS pipeline, we have developed a semi-automatic procedure for magnetic field determination. We have applied this procedure to the full content of circular spectropolarimetric measurements of the FORS1 archive (except for most of the observations obtained in multi-object spectropolarimetric mode). We have devised and applied a number of consistency checks to our field determinations, and we have compared our results to those previously published in the literature.

    Results. We find that for high signal-to-noise ratio measurements, photon noise does not account for the full error bars. We discuss how field measurements depend on the specific algorithm adopted for data reduction, and we show that very small instrument flexures, negligible in most of the instrument applications, may be responsible for some spurious field detections in the null profiles. Finally, we find that we are unable to reproduce some results previously published in the literature. Consequently, we do not confirm some important discoveries of magnetic fields obtained with FORS1 and reported in previous publications.

    Conclusions. Our revised field measurements show that there is no contradiction between the results obtained with the low-resolution spectropolarimeter FORS1 and those obtained with high-resolution spectropolarimeters. FORS1 is an instrument capable of performing reliable magnetic field measurements, provided that the various sources of uncertainties are properly taken into account.

  • 13.
    Bahar, Engin
    et al.
    Ankara Univ, Fac Sci, Dept Astron & Space Sci, TR-06100 Ankara, Turkiye..
    Senavci, Hakan V.
    Ankara Univ, Fac Sci, Dept Astron & Space Sci, TR-06100 Ankara, Turkiye..
    Isik, Emre
    Max Planck Inst Sonnensyst Forsch, Justus von Liebig Weg 3, D-37077 Gottingen, Germany.;Turkish German Univ, Dept Comp Sci, TR-34820 Istanbul, Turkiye..
    Hussain, Gaitee A. J.
    European Space Agcy ESA, European Space Res & Technol Ctr ESTEC, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Montes, David
    Univ Complutense Madrid, Fac Ciencias Fis, Dept Fis Tierra & Astrofis, E-28040 Madrid, Spain.;Univ Complutense Madrid, Fac Ciencias Fis, IPARCOS UCM Inst Fis Particulas & Cosmos UCM, E-28040 Madrid, Spain..
    Xiang, Yue
    Chinese Acad Sci, Yunnan Observ, Kunming 650216, Peoples R China.;Chinese Acad Sci, Key Lab Struct & Evolut Celestial Objects, Kunming, Peoples R China..
    First Chromospheric Activity and Doppler Imaging Study of PW And Using a New Doppler Imaging Code: SpotDIPy2024In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 960, no 1, article id 60Article in journal (Refereed)
    Abstract [en]

    Measuring the coverage of dark spots on cool stars is important to understanding how stellar magnetic activity scales with the rotation rate and convection zone depth. In this respect, it is crucial to infer surface magnetic patterns on G and K stars, to reveal solar-like stellar dynamos in action. Molecular bands serve as invaluable indicators of cool spots on the surfaces of stars, as they play a crucial role in enabling accurate assessments of the extent of spot coverage across the stellar surface. Therefore, more reliable surface images can be obtained considering the inversion of atomic lines with molecular bands. In this context, we simultaneously carry out Doppler imaging (DI) using atomic lines as well as titanium oxide band profiles of PW And (K2 V) and also investigate chromospheric activity indicators for the first time in the literature, using high-resolution spectra. The surface spot distribution obtained from the inversion process represents both atomic line and TiO-band profiles quite accurately. The chromospheric emission is also correlated with photospheric spot coverage, except during a possible flare event during the observations. We detect frequent flare activity, using TESS photometry. We also introduce a new open-source, Python-based DI code SpotDIPy that allows performing surface reconstructions of single stars using the maximum entropy method. We test the code by comparing surface reconstruction simulations with the extensively used DoTS code. We show that the surface brightness distribution maps reconstructed via both codes using the same simulated data are consistent with each other.

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  • 14. Bailey, J. D.
    et al.
    Landstreet, J. D.
    Bagnulo, S.
    Fossati, L.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Paladini, C.
    Silvester, J.
    Wade, G.
    Magnetic field and atmospheric chemical abundances of the magnetic Ap star HD 3181072011In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 535, p. A25-Article in journal (Refereed)
    Abstract [en]

    Context. A new generation of powerful and efficient spectropolarimeters has recently been used to provide the first sample of magnetic Ap stars of accurately known ages. Modelling of these data offer the possibility of significant new insights into the physics and main sequence evolution of these remarkable stars.

    Aims. New spectra have been obtained with the ESPaDOnS spectropolarimeter, and are supplemented with unpolarised spectra from the ESO UVES, UVES-FLAMES, and HARPS spectrographs, of the very peculiar large-field magnetic Ap star HD 318107, a member of the open cluster NGC 6405 and thus a star with a well-determined age. The available data provide sufficient material with which to re-analyse the first-order model of the magnetic field geometry and to derive chemical abundances of Si, Ti, Fe, Nd, Pr, Mg, Cr, Mn, O, and Ca.

    Methods. The models were obtained using ZEEMAN, a program which synthesises spectral line profiles for stars that have magnetic fields. The magnetic field structure was modelled with a low-order colinear multipole expansion, using coefficients derived from the observed variations of the field strength with rotation phase. The abundances of several elements were determined using spectral synthesis. After experiments with a very simple model of uniform abundance on each of three rings of equal width in co-latitude and symmetric about the assumed magnetic axis, we decided to model the spectra assuming uniform abundances of each element over the stellar surface.

    Results. The new magnetic field measurements allow us to refine the rotation period of HD 318107 to P = 9.7088 +/- 0.0007 days. Appropriate magnetic field model parameters were found that very coarsely describe the (apparently rather complex) field moment variations. Spectrum synthesis leads to the derivation of mean abundances for the elements Mg, Si, Ca, Ti, Cr, Fe, Nd, and Pr. All of these elements except for Mg and Ca are strongly overabundant compared to the solar abundance ratios. There is considerable evidence of non-uniformity, for example in the different values of < B(z)> found using lines of different elements.

    Conclusions. The present data set, while limited, is nevertheless sufficient to provide a useful first-order assessment of both the magnetic and surface abundance properties of HD 318107, making it one of the very few magnetic Ap stars of well-known age for which both of these properties have been studied.

  • 15.
    Barklem, Paul
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    O'Mara, B. J.
    Stempels, H. C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Hydrogen Line Formation in Cool Stars2001In: 11th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun / [ed] Garcia Lopez, Ramon J.; Rebolo, Rafael; Zapaterio Osorio, Mario Rosa, San Francisco: Astronomical Society of the Pacific , 2001, p. 766-Conference paper (Other academic)
  • 16.
    Barklem, Paul
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Stempels, H.C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Allende Prieto, C.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    O'Mara, B.J.
    Detailed analysis of Balmer lines in cool dwarf stars2002In: Astronomy & Astrophysics, ISSN 0004-6361, Vol. 385, p. 951-Article in journal (Refereed)
  • 17.
    Barklem, Paul
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Stempels, H.C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    O'Mara, J.B.
    Balmer lines and effective temperatures in cool stars2003In: 12th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, 2003, p. 1103-Conference paper (Other academic)
  • 18.
    Bellotti, S.
    et al.
    Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, IRAP,UMR 5277, 14 Ave Edouard Belin, F-31400 Toulouse, France.;European Space Res & Technol Ctr ESA ESTEC, Sci Div, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Morin, J.
    Univ Montpellier, Lab Univers & Particules Montpellier, CNRS, F-34095 Montpellier, France..
    Lehmann, L. T.
    Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, IRAP,UMR 5277, 14 Ave Edouard Belin, F-31400 Toulouse, France..
    Folsom, C. P.
    Univ Tartu, Tartu Observ, Observatooriumi 1, EE-61602 Toravere, Tartumaa, Estonia..
    Hussain, G. A. J.
    European Space Res & Technol Ctr ESA ESTEC, Sci Div, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Petit, P.
    Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, IRAP,UMR 5277, 14 Ave Edouard Belin, F-31400 Toulouse, France..
    Donati, J.-F.
    Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, IRAP,UMR 5277, 14 Ave Edouard Belin, F-31400 Toulouse, France..
    Lavail, Alexis
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy. Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, IRAP,UMR 5277, 14 Ave Edouard Belin, F-31400 Toulouse, France.
    Carmona, A.
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Martioli, E.
    Lab Nacl Astrofis, Rua Estados Unidos 154, BR-37504364 Itajuba, MG, Brazil.;Sorbonne Univ, Inst Astrophys Paris, CNRS, UMR 7095, 98 Bis Bd Arago, F-75014 Paris, France..
    Romano Zaire, B.
    Univ Fed Minas Gerais, BR-31270901 Belo Horizonte, MG, Brazil..
    Alecian, E.
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Moutou, C.
    Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, IRAP,UMR 5277, 14 Ave Edouard Belin, F-31400 Toulouse, France..
    Fouqué, P.
    Univ Toulouse, Inst Rech Astrophys & Planetol, CNRS, IRAP,UMR 5277, 14 Ave Edouard Belin, F-31400 Toulouse, France..
    Alencar, S.
    Univ Fed Minas Gerais, BR-31270901 Belo Horizonte, MG, Brazil..
    Artigau, E.
    Univ Montreal, Dept Phys, IREX, Montreal, PQ H3C 3J7, Canada..
    Boisse, I.
    Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France..
    Bouchy, F.
    Univ Geneva, Observ Geneve, Chemin Pegasi 51, CH-1290 Sauverny, Switzerland..
    Cadieux, C.
    Univ Montreal, Dept Phys, IREX, Montreal, PQ H3C 3J7, Canada..
    Cloutier, R.
    McMaster Univ, Dept Phys & Astron, 1280 Main St West, Hamilton, ON L8S 4L8, Canada..
    Cook, N. J.
    Univ Montreal, Dept Phys, IREX, Montreal, PQ H3C 3J7, Canada..
    Delfosse, X.
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Doyon, R.
    Univ Montreal, Dept Phys, IREX, Montreal, PQ H3C 3J7, Canada..
    Hébrard, G.
    Sorbonne Univ, Inst Astrophys Paris, CNRS, UMR 7095, 98 Bis Bd Arago, F-75014 Paris, France.;Observ Haute Provence, 1912 Route Observ, F-04870 St Michel Lobservatoire, France..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Wade, G. A.
    Royal Mil Coll Canada, Dept Phys & Space Sci, POB 17000 Stat Force, Kingston, ON K7K 0C6, Canada..
    Monitoring the large-scale magnetic field of AD Leo with SPIRou, ESPaDOnS, and Narval: Towards a magnetic polarity reversal?2023In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 676, article id A56Article in journal (Refereed)
    Abstract [en]

    Context: One clear manifestation of dynamo action on the Sun is the 22-yr magnetic cycle, exhibiting a polarity reversal and a periodic conversion between poloidal and toroidal fields. For M dwarfs, several authors claim evidence of activity cycles from photometry and analyses of spectroscopic indices, but no clear polarity reversal has been identified from spectropolarimetric observations. These stars are excellent laboratories to investigate dynamo-powered magnetic fields under different stellar interior conditions, that is partly or fully convective.

    Aims: Our aim is to monitor the evolution of the large-scale field of AD Leo, which has shown hints of a secular evolution from past dedicated spectropolarimetric campaigns. This is of central interest to inform distinct dynamo theories, contextualise the evolution of the solar magnetic field, and explain the variety of magnetic field geometries observed in the past.

    Methods: We analysed near-infrared spectropolarimetric observations of the active M dwarf AD Leo taken with SPIRou between 2019 and 2020 and archival optical data collected with ESPaDOnS and Narval between 2006 and 2019. We searched for long-term variability in the longitudinal field, the width of unpolarised Stokes profiles, the unsigned magnetic flux derived from Zeeman broadening, and the geometry of the large-scale magnetic field using both Zeeman-Doppler imaging and principal component analysis.

    Results: We found evidence of a long-term evolution of the magnetic field, featuring a decrease in axisymmetry (from 99% to 60%). This is accompanied by a weakening of the longitudinal field (-300 to -50 G) and a correlated increase in the unsigned magnetic flux (2.8-3.6 kG). Likewise, the width of the mean profile computed with selected near-infrared lines manifests a long-term evolution corresponding to field strength changes over the full time series, but does not exhibit modulation with the stellar rotation of AD Leo in individual epochs.

    Conclusions: The large-scale magnetic field of AD Leo manifested first hints of a polarity reversal in late 2020 in the form of a substantially increased dipole obliquity, while the topology remained predominantly poloidal and dipolar for 14 yr. This suggests that low-mass M dwarfs with a dipole-dominated magnetic field can undergo magnetic cycles.

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  • 19. Benedict, G. Fritz
    et al.
    McArthur, Barbara E.
    Feast, Michael W.
    Barnes, Thomas G.
    Harrison, Thomas E.
    Bean, Jacob L.
    Menzies, John W.
    Chaboyer, Brian
    Fossati, Luca
    Nesvacil, Nicole
    Smith, Horace A.
    Kolenberg, Katrien
    Laney, C. D.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Nelan, Edmund P.
    Shulyak, D. V.
    Taylor, Denise
    Freedman, Wendy L.
    Distance scale zero points from galactic RR Lyrae star parallaxes2011In: Astronomical Journal, ISSN 0004-6256, E-ISSN 1538-3881, Vol. 142, no 6, p. 187-Article in journal (Refereed)
    Abstract [en]

    We present new absolute trigonometric parallaxes and proper motions for seven Population II variable stars-five RR Lyr variables: RZ Cep, XZ Cyg, SU Dra, RR Lyr, and UV Oct; and two type 2 Cepheids: VY Pyx and kappa Pav. We obtained these results with astrometric data from Fine Guidance Sensors, white-light interferometers on Hubble Space Telescope. We find absolute parallaxes in milliseconds of arc: RZ Cep, 2.12 +/- 0.16 mas; XZ Cyg, 1.67 +/- 0.17 mas; SU Dra, 1.42 +/- 0.16 mas; RR Lyr, 3.77 +/- 0.13 mas; UV Oct, 1.71 +/- 0.10 mas; VY Pyx, 6.44 +/- 0.23 mas; and. Pav, 5.57 +/- 0.28 mas; an average sigma(pi)/pi = 5.4%. With these parallaxes, we compute absolute magnitudes in V and K bandpasses corrected for interstellar extinction and Lutz-Kelker-Hanson bias. Using these RR Lyrae variable star absolute magnitudes, we then derive zero points for M(V)-[Fe/H] and M(K)-[Fe/H]-log P relations. The technique of reduced parallaxes corroborates these results. We employ our new results to determine distances and ages of several Galactic globular clusters and the distance of the Large Magellanic Cloud. The latter is close to that previously derived from Classical Cepheids uncorrected for any metallicity effect, indicating that any such effect is small. We also discuss the somewhat puzzling results obtained for our two type 2 Cepheids.

  • 20.
    Blazere, Aurore
    et al.
    Univ Liege, Inst Astrophys & Geophys, Quartier Agora B5c, Alle 6 Aout 19c, B-4000 Liege, Belgium;Univ Paris Diderot, PSL Univ, Sorbonne Univ, LESIA,Observ Paris,CNRS,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92195 Meudon, France.
    Petit, Pascal
    Univ Toulouse, UPS, CNRS, CNES,IRAP, F-31400 Toulouse, France.
    Neiner, Coralie
    Univ Paris Diderot, PSL Univ, Sorbonne Univ, LESIA,Observ Paris,CNRS,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92195 Meudon, France.
    Folsom, Colin
    Univ Toulouse, UPS, CNRS, CNES,IRAP, F-31400 Toulouse, France.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Mathis, Stephane
    Univ Paris Diderot, PSL Univ, Sorbonne Univ, LESIA,Observ Paris,CNRS,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92195 Meudon, France;Univ Paris Diderot, IRFU DAp Ctr Saclay, CNRS, Lab AIM Paris Saclay,CEA DRF, F-91191 Gif Sur Yvette, France.
    Deal, Morgan
    Univ Paris Diderot, PSL Univ, Sorbonne Univ, LESIA,Observ Paris,CNRS,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92195 Meudon, France.
    Landstreet, John
    Univ Western Ontario, Dept Phys & Astron, London, ON N6A 3K7, Canada.
    Magnetic geometry and surface differential rotation of the bright Am star Alhena A2020In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 492, no 4, p. 5794-5810Article in journal (Refereed)
    Abstract [en]

    Alhena A (y Gem A) is a bright Am star, with the strongest disc -integrated magnetic field strength reported so far for an Am star. Its spectrum exhibits standard circularly polarized Zeeman signatures, contrary to all previously studied Am stars that display abnormal signatures dominated by a single -signed lobe. We present here the result of follow-up observations of Athena, using very high signal-to-noise spectropolarimetric data obtained over 25 observing nights with NARVAL at Telescope Bernard Lyot, in the frame of the BRITE (BRIght Target Explorer) spectropolarimetric survey. We confirm that Alhena A is magnetic and we determine its surface magnetic properties using different methods. Inclined dipole models are used to reproduce the longitudinal field measurements, as well as the Stokes V line profiles themselves. In both cases, the model is consistent with a polar field strength of 30 G. This is confirmed by a Zeeman -Doppler Imaging (ZDI) model, which also unveils smaller scale magnetic structures. A rotational period of 8.975 d was identified using intensity line profile variations. The ZDI inversion suggests that the surface magnetic field is sheared by differential rotation, with a difference in rotation rate between high and low latitudes at about 15 per cent of the solar value. This result challenges theories of the development of surface differential rotation in intermediate mass main -sequence stars.

  • 21.
    Brown, A. G. A.
    et al.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Vallenari, A.
    Osserv Astron Padova, INAF, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Prusti, T.
    European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Sci Support Off, Keplerlaan 1, NL-2201AZ Noordwijk, Netherlands..
    de Bruijne, J. H. J.
    European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Sci Support Off, Keplerlaan 1, NL-2201AZ Noordwijk, Netherlands..
    Mignard, F.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Drimmel, R.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Babusiaux, C.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Bailer-Jones, C. A. L.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Bastian, U.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Biermann, M.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Evans, D. W.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Eyer, L.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Jansen, F.
    European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Operat Dept, Mission Operat Div, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Jordi, C.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Katz, D.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Klioner, S. A.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Lammers, U.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Lindegren, L.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Luri, X.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    O'Mullane, W.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Panem, C.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Pourbaix, D.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium.;FRS FNRS, Rue Egmont 5, B-1000 Brussels, Belgium..
    Randich, S.
    Osserv Astrofis Arcetri, INAF, Largo Enrico Fermi 5, I-50125 Florence, Italy..
    Sartoretti, P.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Siddiqui, H. I.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo del Castillo, Madrid 28692, Spain..
    Soubiran, C.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Valette, V.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    van Leeuwen, F.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Walton, N. A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Aerts, C.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium.;Radboud Univ Nijmegen, IMAPP, Dept Astrophys, POB 9010, NL-6500 GL Nijmegen, Netherlands..
    Arenou, F.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Cropper, M.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England..
    Hog, E.
    Univ Copenhagen, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen O, Denmark..
    Lattanzi, M. G.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Grebel, E. K.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Holland, A. D.
    Open Univ, Dept Phys Sci, Ctr Elect Imaging, Walton Hall, Milton Keynes MK7 6AA, Bucks, England..
    Huc, C.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Passot, X.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Perryman, M.
    European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Sci Support Off, Keplerlaan 1, NL-2201AZ Noordwijk, Netherlands..
    Bramante, L.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Cacciari, C.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Castaneda, J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Chaoul, L.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Cheek, N.
    Serco Gest Negocios ESA ESAC, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    De Angeli, F.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Fabricius, C.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Guerra, R.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Hernandez, J.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Jean-Antoine-Piccolo, A.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Masana, E.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Messineo, R.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Mowlavi, N.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Nienartowicz, K.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Ordonez-Blanco, D.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Panuzzo, P.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Portell, J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Richards, P. J.
    Rutherford Appleton Lab, STFC, Didcot OX11 0QX, Oxon, England..
    Riello, M.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Seabroke, G. M.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England..
    Tanga, P.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Thevenin, F.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Torra, J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Els, S. G.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany.;ESAC, Gaia DPAC Project Off, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Gracia-Abril, G.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain.;ESAC, Gaia DPAC Project Off, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Comoretto, G.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo del Castillo, Madrid 28692, Spain..
    Garcia-Reinaldos, M.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Lock, T.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Mercier, E.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany.;ESAC, Gaia DPAC Project Off, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Altmann, M.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany.;UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France..
    Andrae, R.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Astraatmadja, T. L.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Bellas-Velidis, I.
    Natl Observ Athens, Athens 15236, Greece..
    Benson, K.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England..
    Berthier, J.
    UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Blomme, R.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Busso, G.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Carry, B.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France.;UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Cellino, A.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Clementini, G.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Cowell, S.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Creevey, O.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France.;Univ Paris XI, CNRS, Inst Astrophys Spatiale, UMR 8617, Batiment 121, F-91405 Orsay, France..
    Cuypers, J.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Davidson, M.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    De Ridder, J.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium..
    de Torres, A.
    ESA ESAC, HE Space Operat BV, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Delchambre, L.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Dell'Oro, A.
    Osserv Astrofis Arcetri, INAF, Largo Enrico Fermi 5, I-50125 Florence, Italy..
    Ducourant, C.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Fremat, Y.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Garcia-Torres, M.
    Univ Pablo de Olavide, Area Lenguajes & Sistemas Informat, Ctra Utrera,Km 1, Seville 41013, Spain..
    Gosset, E.
    FRS FNRS, Rue Egmont 5, B-1000 Brussels, Belgium.;Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Halbwachs, J. -L
    Hambly, N. C.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Harrison, D. L.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England.;Univ Cambridge, Kavli Inst Cosmol, Madingley Rd, Cambridge CB3 0HA, England..
    Hauser, M.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Hestroffer, D.
    UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Hodgkin, S. T.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Huckle, H. E.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England..
    Hutton, A.
    ESA ESAC, Aurora Technol, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Jasniewicz, G.
    Univ Montpellier, Lab Univers & Particules Montpellier, Pl Eugene Bataillon,CC72, F-34095 Montpellier 05, France..
    Jordan, S.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Kontizas, M.
    Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Korn, Andreas J.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Lanzafame, A. C.
    Univ Catania, Dipartimento Fis & Astron, Sez Astrofis, Via S Sofia 78, I-95123 Catania, Italy.;Osserv Astrofis Catania, INAF, Via S Sofia 78, I-95123 Catania, Italy..
    Manteiga, M.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Moitinho, A.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Muinonen, K.
    Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland.;Finnish Geospatial Res Inst FGI, Geodeetinrinne 2, Masala 02430, Finland..
    Osinde, J.
    ESA ESAC, Isdefe, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Pancino, E.
    Osserv Astrofis Arcetri, INAF, Largo Enrico Fermi 5, I-50125 Florence, Italy.;ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy..
    Pauwels, T.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Petit, J. -M
    Recio-Blanco, A.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Robin, A. C.
    Univ Bourgogne Franche Comte, OSU THETA Franche Comte Bourgogne, CNRS, Inst UTINAM UMR6213, F-25000 Besancon, France..
    Sarro, L. M.
    UNED, Dept Inteligencia Artificial, C Juan del Rosal 16, Madrid 28040, Spain..
    Siopis, C.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium..
    Smith, M.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England..
    Smith, K. W.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Sozzetti, A.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Thuillot, W.
    UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    van Reeven, W.
    ESA ESAC, Aurora Technol, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Viala, Y.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Abbas, U.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Aramburu, A. Abreu
    ESA ESAC, Elecnor Deimos Space, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Accart, S.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Aguado, J. J.
    UNED, Dept Inteligencia Artificial, C Juan del Rosal 16, Madrid 28040, Spain..
    Allan, P. M.
    Rutherford Appleton Lab, STFC, Didcot OX11 0QX, Oxon, England..
    Allasia, W.
    EURIX Srl, Via Carcano 26, I-10153 Turin, Italy..
    Altavilla, G.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Alvarez, M. A.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Alves, J.
    Univ Vienna, Dept Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria..
    Anderson, R. I.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland.;Johns Hopkins Univ, Dept Phys & Astron, 3400 N Charles St, Baltimore, MD 21218 USA..
    Andrei, A. H.
    UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France.;ON MCTI BR, Rua Gal Jose Cristino 77, BR-20921400 Rio De Janeiro, RJ, Brazil.;OV UFRJ BR, Ladeira Pedro Antonio 43, BR-20080090 Rio De Janeiro, RJ, Brazil..
    Varela, E. Anglada
    Serco Gest Negocios ESA ESAC, Camino Bajo del Castillo S-N, Madrid 28692, Spain.;ESA ESAC, Isdefe, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Antiche, E.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Antoja, T.
    European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Sci Support Off, Keplerlaan 1, NL-2201AZ Noordwijk, Netherlands..
    Anton, S.
    Univ Porto, Fac Ciencias, Dept Matemat, Rua Campo Alegre 687, P-4169007 Oporto, Portugal.;Univ Lisbon, Inst Astrofis & Ciencias Espaco, Fac Ciencias, P-1749016 Lisbon, Portugal..
    Arcay, B.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Bach, N.
    ESA ESAC, Aurora Technol, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Baker, S. G.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England..
    Balaguer-Nunez, L.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Barache, C.
    UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France..
    Barata, C.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Barbier, A.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Barblan, F.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Barrado y Navascues, D.
    ESA ESAC, Ctr Astrobiol CSIC INTA, Dept Astrofis, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Barros, M.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Barstow, M. A.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Becciani, U.
    Osserv Astrofis Catania, INAF, Via S Sofia 78, I-95123 Catania, Italy..
    Bellazzini, M.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Garcia, A. Bello
    Univ Oviedo, Campus Univ, Gijon 33203, Spain..
    Belokurov, V.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Bendjoya, P.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Berihuete, A.
    Univ Cadiz, Avd Univ, Cadiz 11002, Spain..
    Bianchi, L.
    EURIX Srl, Via Carcano 26, I-10153 Turin, Italy..
    Bienayme, O.
    Univ Strasbourg, Observ Astron Strasbourg, CNRS, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France..
    Billebaud, F.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Blagorodnova, N.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Blanco-Cuaresma, S.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland.;Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Boch, T.
    Univ Strasbourg, Observ Astron Strasbourg, CNRS, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France..
    Bombrun, A.
    ESA ESAC, HE Space Operat BV, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Borrachero, R.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Bouquillon, S.
    UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France..
    Bourda, G.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Bouy, H.
    ESA ESAC, Ctr Astrobiol CSIC INTA, Dept Astrofis, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Bragaglia, A.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Breddels, M. A.
    Univ Groningen, Kapteyn Astron Inst, Landleven 12, NL-9747 AD Groningen, Netherlands..
    Brouillet, N.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Bruesemeister, T.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Bucciarelli, B.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Burgess, P.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Burgon, R.
    Open Univ, Dept Phys Sci, Ctr Elect Imaging, Walton Hall, Milton Keynes MK7 6AA, Bucks, England..
    Burlacu, A.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Busonero, D.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Buzzi, R.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Caffau, E.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Cambras, J.
    Univ Catalunya, Consorci Serv, C Gran Capita 2-4 3rd Floor, Barcelona 08034, Spain..
    Campbell, H.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Cancelliere, R.
    Univ Turin, Dept Comp Sci, Corso Svizzera 185, I-10149 Turin, Italy..
    Cantat-Gaudin, T.
    Osserv Astron Padova, INAF, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Carlucci, T.
    UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France..
    Carrasco, J. M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Castellani, M.
    Osserv Astron Roma, INAF, Via Frascati 33, I-00078 Rome, Italy..
    Charlot, P.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Charnas, J.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Chiavassa, A.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Clotet, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Cocozza, G.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Collins, R. S.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Costigan, G.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Crifo, F.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Cross, N. J. G.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Crosta, M.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Crowley, C.
    ESA ESAC, HE Space Operat BV, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Dafonte, C.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Damerdji, Y.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium.;CRAAG, Route Observ,BP 63 Bouzareah, Algiers 16340, Algeria..
    Dapergolas, A.
    Natl Observ Athens, Athens 15236, Greece..
    David, P.
    UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    David, M.
    Univ Antwerp, Onderzoeksgrp Toegepaste Wiskunde, Middelheimlaan 1, B-2020 Antwerp, Belgium..
    De Cat, P.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    de Felice, F.
    Univ Padua, Dept Phys & Astron, Via Marzolo 8, I-35131 Padua, Italy..
    de laverny, P.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    De Luise, F.
    Osservatorio Astron Teramo, INAF, Via Mentore Maggini, I-64100 Teramo, Italy..
    De March, R.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    de Martino, D.
    Osserv Astron Capodimonte, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    de Souza, R.
    Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Rua Matao,1226 Cidade Univ, BR-05508900 Sao Paulo, SP, Brazil..
    Debosscher, J.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium..
    del Pozo, E.
    ESA ESAC, Aurora Technol, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Delbo, M.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Delgado, A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Delgado, H. E.
    UNED, Dept Inteligencia Artificial, C Juan del Rosal 16, Madrid 28040, Spain..
    Di Matteo, P.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Diakite, S.
    Univ Bourgogne Franche Comte, OSU THETA Franche Comte Bourgogne, CNRS, Inst UTINAM UMR6213, F-25000 Besancon, France..
    Distefano, E.
    Osserv Astrofis Catania, INAF, Via S Sofia 78, I-95123 Catania, Italy..
    Dolding, C.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England..
    Dos Anjos, S.
    Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Rua Matao,1226 Cidade Univ, BR-05508900 Sao Paulo, SP, Brazil..
    Drazinos, P.
    Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Duran, J.
    ESA ESAC, Isdefe, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Dzigan, Y.
    Tel Aviv Univ, Dept Geosci, IL-6997801 Tel Aviv, Israel.;Univ Amsterdam, Astron Inst Anton Pannekoek, POB 94249, NL-1090 GE Amsterdam, Netherlands..
    Edvardsson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Enke, H.
    Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    Evans, N. W.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Bontemps, G. Eynard
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Fabre, C.
    CNES Ctr Spatial Toulouse, ATOS, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Fabrizio, M.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy.;Osservatorio Astron Teramo, INAF, Via Mentore Maggini, I-64100 Teramo, Italy..
    Faigler, S.
    Tel Aviv Univ, Sch Phys & Astron, IL-6997801 Tel Aviv, Israel..
    Falcao, A. J.
    UNINOVA CTS, Campus FCT UNL, P-2829516 Caparica, Portugal..
    Casas, M. Farras
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Federici, L.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Fedorets, G.
    Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland..
    Fernandez-Hernandez, J.
    Serco Gest Negocios ESA ESAC, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Fernique, P.
    Univ Strasbourg, Observ Astron Strasbourg, CNRS, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France..
    Fienga, A.
    Univ Nice Sophia Antipolis, Lab Geoazur, UMR 7329, CNRS,Observ Cote dAzur, 250 Rue A Einstein, F-06560 Valbonne, France..
    Figueras, F.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Filippi, F.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Findeisen, K.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Fonti, A.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Fouesneau, M.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Fraile, E.
    ESA ESAC, RHEA, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Fraser, M.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Fuchs, J.
    Acad Sci Czech Republic, Astron Inst, Fricova 298, Ondrejov 25165, Czech Republic..
    Gai, M.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Galleti, S.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Galluccio, L.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Garabato, D.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Garcia-Sedano, F.
    UNED, Dept Inteligencia Artificial, C Juan del Rosal 16, Madrid 28040, Spain..
    Garofalo, A.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Garralda, N.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Gavras, P.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;Natl Observ Athens, Athens 15236, Greece.;Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Gerssen, J.
    Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    Geyer, R.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Gilmore, G.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Girona, S.
    Barcelona Supercomp Ctr, Centro Nacl Supercomp, C Jordi Girona 29,Ed Nexus 2, Barcelona 08034, Spain..
    Giuffrida, G.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy..
    Gomes, M.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Gonzalez-Marcos, A.
    Univ La Rioja, Dept Mech Engn, C San Jose de Calasanz 31, Logrono 26004, La Rioja, Spain..
    Gonzalez-Nunez, J.
    Serco Gest Negocios ESA ESAC, Camino Bajo del Castillo S-N, Madrid 28692, Spain.;Univ Vigo, ETSE Telecomunicac, Campus Lagoas Marcosende, Vigo 36310, Galicia, Spain..
    Gonzalez-Vidal, J. J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Granvik, M.
    Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland..
    Guerrier, A.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Guillout, P.
    Univ Strasbourg, Observ Astron Strasbourg, CNRS, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France..
    Guiraud, J.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Gurpide, A.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Gutierrez-Sanchez, R.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo del Castillo, Madrid 28692, Spain..
    Guy, L. P.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Haigron, R.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Hatzidimitriou, D.
    Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Haywood, M.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Heiter, Ulrike
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Helmi, A.
    Univ Groningen, Kapteyn Astron Inst, Landleven 12, NL-9747 AD Groningen, Netherlands..
    Hobbs, D.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Hofmann, W.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Holl, B.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Holland, G.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Hunt, J. A. S.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England..
    Hypki, A.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Icardi, V.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Irwin, M.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    de Fombelle, G. Jevardat
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Jofre, P.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England.;Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Jonker, P. G.
    Radboud Univ Nijmegen, IMAPP, Dept Astrophys, POB 9010, NL-6500 GL Nijmegen, Netherlands.;SRON Netherlands Inst Space Res, SRON, Sorbonnelaan 2, NL-3584 CA Utrecht, Netherlands..
    Jorissen, A.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium..
    Julbe, F.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Karampelas, A.
    Natl Observ Athens, Athens 15236, Greece.;Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Kochoska, A.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia..
    Kohley, R.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Kolenberg, K.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium.;Univ Antwerp, Dept Phys, Groenenborgerlaan 171, B-2020 Antwerp, Belgium.;Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA..
    Kontizas, E.
    Natl Observ Athens, Athens 15236, Greece..
    Koposov, S. E.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Kordopatis, G.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France.;Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    Koubsky, P.
    Acad Sci Czech Republic, Astron Inst, Fricova 298, Ondrejov 25165, Czech Republic..
    Krone-Martins, A.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Kudryashova, M.
    UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Kull, I.
    Tel Aviv Univ, Sch Phys & Astron, IL-6997801 Tel Aviv, Israel..
    Bachchan, R. K.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Lacoste-Seris, F.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Lanza, A. F.
    Osserv Astrofis Catania, INAF, Via S Sofia 78, I-95123 Catania, Italy..
    Lavigne, J. -B
    Le Poncin-Lafitte, C.
    UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France..
    Lebreton, Y.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;Univ Rennes 1, Inst Phys Rennes, F-35042 Rennes, France..
    Lebzelter, T.
    Univ Vienna, Dept Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria..
    Leccia, S.
    Osserv Astron Capodimonte, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    Leclerc, N.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Lecoeur-Taibi, I.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Lemaitre, V.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Lenhardt, H.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Leroux, F.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Liao, S.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy.;Chinese Acad Sci, Shanghai Astron Observ, 80 Nandan Rd, Shanghai 200030, Peoples R China..
    Licata, E.
    EURIX Srl, Via Carcano 26, I-10153 Turin, Italy..
    Lindstrom, H. E. P.
    Univ Copenhagen, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen O, Denmark.;CSC Danmark AS, Retortvej 8, DK-2500 Valby, Denmark..
    Lister, T. A.
    Las Cumbres Observ Global Telescope Network Inc, 6740 Cortona Dr,Suite 102, Goleta, CA 93117 USA..
    Livanou, E.
    Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Lobel, A.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Loeffler, W.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Lopez, M.
    ESA ESAC, Ctr Astrobiol CSIC INTA, Dept Astrofis, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Lorenz, D.
    Univ Vienna, Dept Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria..
    MacDonald, I.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Fernandes, T. Magalhacs
    UNINOVA CTS, Campus FCT UNL, P-2829516 Caparica, Portugal..
    Managau, S.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Mann, R. G.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Mantelet, G.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Marchal, O.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Marchant, J. M.
    Liverpool John Moores Univ, Astrophys Res Inst, Liverpool L3 5RF, Merseyside, England..
    Marconi, M.
    Osserv Astron Capodimonte, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    Marinoni, S.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy.;Osserv Astron Roma, INAF, Via Frascati 33, I-00078 Rome, Italy..
    Marrese, P. M.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy.;Osserv Astron Roma, INAF, Via Frascati 33, I-00078 Rome, Italy..
    Marschalko, G.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary.;Univ Szeged, Baja Observ, Szegedi Ut 3-70, H-6500 Baja, Hungary..
    Marshall, D. J.
    Univ Paris Diderot, CEA Saclay, CEA DSM CNRS, IRFU,Serv Astrophys,Lab AIM, Bat 709, F-91191 Gif Sur Yvette, France..
    Martin-Fleitas, J. M.
    ESA ESAC, Aurora Technol, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Martino, M.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Mary, N.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Matijevic, G.
    Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    Mazeh, T.
    Tel Aviv Univ, Sch Phys & Astron, IL-6997801 Tel Aviv, Israel..
    McMillan, P. J.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Messina, S.
    Osserv Astrofis Catania, INAF, Via S Sofia 78, I-95123 Catania, Italy..
    Michalik, D.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Millar, N. R.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Miranda, B. M. H.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Molina, D.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Molinaro, R.
    Osserv Astron Capodimonte, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    Molinaro, M.
    Osserv Astron Trieste, INAF, Via GB Tiepolo 11, I-34143 Trieste, Italy..
    Molnar, L.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary..
    Moniez, M.
    Univ Paris Saclay, CNRS IN2P3, Univ Paris Sud, Lab Accelerateur Lineaire, F-91898 Orsay, France..
    Montegriffo, P.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Mor, R.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Mora, A.
    ESA ESAC, Aurora Technol, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Morbidelli, R.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Morel, T.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Morgenthaler, S.
    Ecole Polytech Fed Lausanne, SB MATHAA STAP, MA B1 473,Batiment MA,Stn 8, CH-1015 Lausanne, Switzerland..
    Morris, D.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Mulone, A. F.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Muraveva, T.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Musella, I.
    Osserv Astron Capodimonte, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    Narbonne, J.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Nelemans, G.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium.;Radboud Univ Nijmegen, IMAPP, Dept Astrophys, POB 9010, NL-6500 GL Nijmegen, Netherlands..
    Nicastro, L.
    INAF IASF Bologna, Via P Gobetti 101, I-40129 Bologna, Italy..
    Noval, L.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Ordenovic, C.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Ordieres-Mere, J.
    Tech Univ Madrid, Jose Gutierrez Abascal 2, Madrid 28006, Spain..
    Osborne, P.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Pagani, C.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Pagano, I.
    Osserv Astrofis Catania, INAF, Via S Sofia 78, I-95123 Catania, Italy..
    Pailler, F.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Palacin, H.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Palaversa, L.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Parsons, P.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo del Castillo, Madrid 28692, Spain..
    Pecoraro, M.
    EURIX Srl, Via Carcano 26, I-10153 Turin, Italy..
    Pedrosa, R.
    CNES Ctr Spatial Toulouse, EQUERT Int, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Pentikainen, H.
    Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland..
    Pichon, B.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Piersimoni, A. M.
    Osservatorio Astron Teramo, INAF, Via Mentore Maggini, I-64100 Teramo, Italy..
    Pincau, F. -X
    Plachy, E.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary..
    Plum, G.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Poujoulet, E.
    CNES Ctr Spatial Toulouse, AKKA, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Prsa, A.
    Villanova Univ, Dept Astrophys & Planetary Sci, 800 E Lancaster Ave, Villanova, PA 19085 USA..
    Pulone, L.
    Osserv Astron Roma, INAF, Via Frascati 33, I-00078 Rome, Italy..
    Ragaini, S.
    Osservatorio Astron Bologna, INAF, Via Ranzani 1, I-40127 Bologna, Italy..
    Rago, S.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Rambaux, N.
    UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Ramos-Lerate, M.
    ESA ESAC, Vitrociset Belgium, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Ranalli, P.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Rauw, G.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Read, A.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Regibo, S.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium..
    Reyle, C.
    Univ Bourgogne Franche Comte, OSU THETA Franche Comte Bourgogne, CNRS, Inst UTINAM UMR6213, F-25000 Besancon, France..
    Ribeiro, R. A.
    UNINOVA CTS, Campus FCT UNL, P-2829516 Caparica, Portugal..
    Rimoldini, L.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Ripepi, V.
    Osserv Astron Capodimonte, INAF, Via Moiariello 16, I-80131 Naples, Italy..
    Riva, A.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Rixon, G.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Roelens, M.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Romero-Gomez, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Rowell, N.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Royer, F.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Ruiz-Dern, L.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Sadowski, G.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium..
    Selles, T. Sagrista
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Sahlmann, J.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Salgado, J.
    ESA ESAC, Isdefe, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Salguero, E.
    ESA ESAC, Isdefe, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Sarasso, M.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Savietto, H.
    Fork Res, Rua Cruzado Osberno,Lt 1,9 Esq, Lisbon, Portugal..
    Schultheis, M.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Sciacca, E.
    Osserv Astrofis Catania, INAF, Via S Sofia 78, I-95123 Catania, Italy..
    Segol, M.
    CNES Ctr Spatial Toulouse, APAVE SUDEUROPE SAS, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Segovia, J. C.
    Serco Gest Negocios ESA ESAC, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Segransan, D.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Shih, I. -C
    Smareglia, R.
    Osserv Astron Trieste, INAF, Via GB Tiepolo 11, I-34143 Trieste, Italy..
    Smart, R. L.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Solano, E.
    ESA ESAC, Ctr Astrobiol CSIC INTA, Dept Astrofis, Camino Bajo del Castillo S-N, Madrid 28692, Spain.;Spanish Virtual Observ, Granada, Spain..
    Solitro, F.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Sordo, R.
    Osserv Astron Padova, INAF, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Nieto, S. Soria
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Souchay, J.
    UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France..
    Spagna, A.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Spoto, F.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Stampa, U.
    Heidelberg Univ, Astron Rechen Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Steele, I. A.
    Liverpool John Moores Univ, Astrophys Res Inst, Liverpool L3 5RF, Merseyside, England..
    Steidelmueller, H.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Stephenson, C. A.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo del Castillo, Madrid 28692, Spain..
    Stoev, H.
    INAF, Fdn Galileo Galilei, Rambla Jose Ana Fernandez Perez 7, Brena Baja 38712, Santa Cruz De T, Spain..
    Suess, F. F.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Suveges, M.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Surdej, J.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Szabados, L.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary..
    Szegedi-Elek, E.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary..
    Tapiador, D.
    ESA ESAC, INSA, Camino Bajo del Castillo S-N, Madrid 28692, Spain.;Univ Complutense Madrid, Dept Arquitectura Comp & Automat, Fac Informat, C Prof Jose Garcia Santesmases S-N, E-28040 Madrid, Spain..
    Taris, F.
    UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France..
    Tauran, G.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Taylor, M. B.
    Univ Bristol, HH Wills Phys Lab, Tyndall Ave, Bristol BS8 1TL, Avon, England..
    Teixeira, R.
    Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Rua Matao,1226 Cidade Univ, BR-05508900 Sao Paulo, SP, Brazil..
    Terrett, D.
    Rutherford Appleton Lab, STFC, Didcot OX11 0QX, Oxon, England..
    Tingley, B.
    Aarhus Univ, Stellar Astrophys Ctr, Dept Phys & Astron, 120 Ny Munkegade,Bldg 1520, DK-8000 Aarhus C, Denmark..
    Trager, S. C.
    Univ Groningen, Kapteyn Astron Inst, Landleven 12, NL-9747 AD Groningen, Netherlands..
    Turon, C.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Ulla, A.
    Univ Vigo, Dept Appl Phys, Vigo 36310, Spain..
    Utrilla, E.
    ESA ESAC, Aurora Technol, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Valentini, G.
    Osservatorio Astron Teramo, INAF, Via Mentore Maggini, I-64100 Teramo, Italy..
    van Elteren, A.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Van Hemelryck, E.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    van Leeuwen, M.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Varadi, M.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland.;Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary..
    Vecchiato, A.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Veljanoski, J.
    Univ Groningen, Kapteyn Astron Inst, Landleven 12, NL-9747 AD Groningen, Netherlands..
    Via, T.
    Univ Catalunya, Consorci Serv, C Gran Capita 2-4 3rd Floor, Barcelona 08034, Spain..
    Vicente, D.
    Barcelona Supercomp Ctr, Centro Nacl Supercomp, C Jordi Girona 29,Ed Nexus 2, Barcelona 08034, Spain..
    Vogt, S.
    ESA ESTEC, HE Space Operat BV, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Voss, H.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Votruba, V.
    Acad Sci Czech Republic, Astron Inst, Fricova 298, Ondrejov 25165, Czech Republic..
    Voutsinas, S.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Walmsley, G.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Weiler, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Weingrill, K.
    Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    Wevers, T.
    Radboud Univ Nijmegen, IMAPP, Dept Astrophys, POB 9010, NL-6500 GL Nijmegen, Netherlands..
    Wyrzykowski, L.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England.;Univ Warsaw Observ, Al Ujazdowskie 4, PL-00478 Warsaw, Poland..
    Yoldas, A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Zerjal, M.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia..
    Zucker, S.
    Tel Aviv Univ, Dept Geosci, IL-6997801 Tel Aviv, Israel..
    Zurbach, C.
    Univ Montpellier, Lab Univers & Particules Montpellier, Pl Eugene Bataillon,CC72, F-34095 Montpellier 05, France..
    Zwitter, T.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia..
    Alecu, A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Allen, M.
    European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Sci Support Off, Keplerlaan 1, NL-2201AZ Noordwijk, Netherlands..
    Prieto, C. Allende
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England.;Inst Astrofis Canarias, Tenerife 38205, Spain.;Univ La Laguna, Dept Astrofis, Tenerife 38206, Spain..
    Amorim, A.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Anglada-Escude, G.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
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    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Azaz, S.
    European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Sci Support Off, Keplerlaan 1, NL-2201AZ Noordwijk, Netherlands..
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    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo del Castillo, Madrid 28692, Spain..
    Beck, M.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Bernstein, H. -H
    Bigot, L.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
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    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Blasco, C.
    ESA ESTEC, RHEA, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
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    Osservatorio Astron Teramo, INAF, Via Mentore Maggini, I-64100 Teramo, Italy..
    Bono, G.
    Osserv Astron Roma, INAF, Via Frascati 33, I-00078 Rome, Italy..
    Boudreault, S.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England.;Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, D-37077 Gottingen, Germany..
    Bressan, A.
    SISSA, Via Bonomea 265, I-34136 Trieste, Italy..
    Brown, S.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Brunet, P. -M
    Bunclark, P.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Buonanno, R.
    Osserv Astron Roma, INAF, Via Frascati 33, I-00078 Rome, Italy..
    Butkevich, A. G.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Carret, C.
    CNES Ctr Spatial Toulouse, EQUERT Int, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Carrion, C.
    UNED, Dept Inteligencia Artificial, C Juan del Rosal 16, Madrid 28040, Spain..
    Chemin, L.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France.;Minist Ciencia Tecnol, Inst Nacl Pesquisas Espaciais, Ave Astronautas 1758, BR-12227010 Sao Jose Dos Campos, SP, Brazil..
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    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Corcione, L.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Darmigny, E.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    de Boer, K. S.
    Univ Bonn, Argelander Inst Astron, Hugel 71, D-53121 Bonn, Germany..
    de Teodoro, P.
    Serco Gest Negocios ESA ESAC, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    de Zeeuw, P. T.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands.;European Southern Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany..
    Delle Luche, C.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Domingues, C. D.
    Univ Lisbon, Lab Opt Lasers & Syst, Fac Sci, Campus Lumiar,Estr Paco Lumiar 22, P-1649038 Lisbon, Portugal..
    Dubath, P.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Fodor, F.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Frezouls, B.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Fries, A.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Fustes, D.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Fyfe, D.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Gallardo, E.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Gallegos, J.
    Serco Gest Negocios ESA ESAC, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Gardiol, D.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Gebran, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain.;Notre Dame Univ, Dept Phys & Astron, POB 72, Zouk Mikael, Lebanon..
    Gomboc, A.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia.;Univ Nova Gorica, Vipavska 13, Nova Gorica 5000, Slovenia..
    Gomez, A.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Grux, E.
    Univ Bourgogne Franche Comte, OSU THETA Franche Comte Bourgogne, CNRS, Inst UTINAM UMR6213, F-25000 Besancon, France..
    Gueguen, A.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;OPINAS, Max Planck Inst Extraterr Phys, Giessenbachstr, D-85741 Garching, Germany..
    Heyrovsky, A.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Hoar, J.
    European Space Astron Ctr ESA ESAC, Camino Bajo dell Castillo S-N, Madrid 28692, Spain..
    Iannicola, G.
    Osserv Astron Roma, INAF, Via Frascati 33, I-00078 Rome, Italy..
    Parache, Y. Isasi
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Janotto, A. -M
    Joliet, E.
    ESA ESAC, HE Space Operat BV, Camino Bajo del Castillo S-N, Madrid 28692, Spain.;CALTECH, NASA IPAC Infrared Sci Arch, Mail Code 100-22,770 South Wilson Ave, Pasadena, CA 91125 USA..
    Jonckheere, A.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Keil, R.
    Univ Bremen, Ctr Appl Space Technol & Micrograv ZARM, Fallturm 1, D-28359 Bremen, Germany.;ESA ESOC, RHEA Syst, Robert Bosch Str 5, D-64293 Darmstadt, Germany..
    Kim, D. -W
    Klagyivik, P.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary..
    Klar, J.
    Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    Knude, J.
    Univ Copenhagen, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen O, Denmark..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Kolka, I.
    Tartu Observ, EE-61602 Toravere, Estonia..
    Kos, J.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia.;Univ Sydney, Sch Phys A28, Sydney Inst Astron, Sydney, NSW 2006, Australia..
    Kutka, A.
    Acad Sci Czech Republic, Astron Inst, Fricova 298, Ondrejov 25165, Czech Republic.;Slovak Org Space Activ, Zamocka 18, Bratislava 85101, Slovakia..
    Lainey, V.
    UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    LeBouquin, D.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Liu, C.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany.;Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China..
    Loreggia, D.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Makarov, V. V.
    US Naval Observ, Astrometry Dept, 3450 Massachusetts Ave NW, Washington, DC 20392 USA..
    Marseille, M. G.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Martayan, C.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium.;European Southern Observ, Alonso de Cordova 3107, Casilla 19001, Santiago De Chi, Chile..
    Martinez-Rubi, O.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Massart, B.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France.;CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France.;Airbus Def & Space SAS, 31 Rue Cosmonautes, F-31402 Toulouse 4, France..
    Meynadier, F.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;UPMC Univ Paris 06, PSL Res Univ, CNRS, SYRTE,Observ Paris,Sorbonne Univ,LNE, 61 Ave Observ, F-75014 Paris, France..
    Mignot, S.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Munari, U.
    Osserv Astron Padova, INAF, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Nguyen, A. -T
    Nordlander, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Ocvirk, P.
    Univ Strasbourg, Observ Astron Strasbourg, CNRS, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France.;Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    O'Flaherty, K. S.
    ESA ESTEC, EJR Quartz BV, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Sanz, A. Olias
    ESA ESAC, Server Labs, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Ortiz, P.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Osorio, J.
    Univ Porto, Fac Ciencias, Dept Matemat, Rua Campo Alegre 687, P-4169007 Oporto, Portugal..
    Oszkiewicz, D.
    Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland.;Adam Mickiewicz Univ, Fac Phys, Astron Observ Inst, Ul Sloneczna 36, PL-60286 Poznan, Poland..
    Ouzounis, A.
    Univ Edinburgh, Royal Observ, Inst Astron, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Palmer, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Park, P.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Pasquato, E.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium..
    Peltzer, C.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Peralta, J.
    Peturaud, F.
    Univ Paris Diderot, PSL Res Univ, CNRS, GEPI,Observ Paris,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Pieniluoma, T.
    Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland..
    Pigozzi, E.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Poels, J.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Prat, G.
    CNES Ctr Spatial Toulouse, CS Syst Informat, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Prod'homme, T.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands.;European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Raison, F.
    OPINAS, Max Planck Inst Extraterr Phys, Giessenbachstr, D-85741 Garching, Germany.;ESA ESAC, Praesepe BV, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Rebordao, J. M.
    Univ Lisbon, Lab Opt Lasers & Syst, Fac Sci, Campus Lumiar,Estr Paco Lumiar 22, P-1649038 Lisbon, Portugal..
    Risquez, D.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Rocca-Volmerange, B.
    UPMC, Sorbonne Univ, F-75014 Paris, France.;Inst Astrophys Paris, CNRS, UMR7095, F-75014 Paris, France..
    Rosen, S.
    Univ Coll London, Mullard Space Sci Lab, Surrey RH5 6NT, England.;Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Ruiz-Fuertes, M. I.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Russo, F.
    Osserv Astron Torino, INAF, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Sembay, S.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Vizcaino, I. Serraller
    ESA ESAC, GMV, Camino Bajo del Castillo S-N, Madrid 28692, Spain..
    Short, A.
    European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Sci Support Off, Keplerlaan 1, NL-2201AZ Noordwijk, Netherlands..
    Siebert, A.
    Univ Strasbourg, Observ Astron Strasbourg, CNRS, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France.;Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    Silva, H.
    UNINOVA CTS, Campus FCT UNL, P-2829516 Caparica, Portugal..
    Sinachopoulos, D.
    Natl Observ Athens, Athens 15236, Greece..
    Slezak, E.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote dAzur, CNRS, CS 34229, F-06304 Nice, France..
    Soffel, M.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Sosnowska, D.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Straizys, V.
    Vilnius Univ, Inst Theoret Phys & Astron, Sauletekio Al 3, LT-10222 Vilnius, Lithuania..
    ter Linden, M.
    ESA ESAC, HE Space Operat BV, Camino Bajo del Castillo S-N, Madrid 28692, Spain.;S&T Corp, POB 608, NL-2600 AP Delft, Netherlands..
    Terrell, D.
    Southwest Res Inst SwRI, Dept Space Studies, 1050 Walnut St,Suite 300, Boulder, CO 80302 USA..
    Theil, S.
    Inst Space Syst, Deutsch Zentrum Luft & Raumfahrt, Fallturm 1, D-28359 Bremen, Germany..
    Tiede, C.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany.;Univ Appl Sci Munich, Karlstr 6, D-80333 Munich, Germany..
    Troisi, L.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy.;Univ Roma Tor Vergata, Dipartimento Fis, Via Ric Sci 1, I-00133 Rome, Italy..
    Tsalmantza, P.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Tur, D.
    Univ Catalunya, Consorci Serv, C Gran Capita 2-4 3rd Floor, Barcelona 08034, Spain..
    Vaccari, M.
    Univ Western Cape, Dept Phys & Astron, Robert Sobukwe Rd, ZA-7535 Cape Town, South Africa.;INAF Ist Radioastron, Via Gobetti 101, I-40129 Bologna, Italy..
    Vachier, F.
    UPMC Univ Paris 06, PSL Res Univ, IMCCE, Observ Paris,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Valles, P.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, E-08028 Barcelona, Spain..
    Van Hamme, W.
    Florida Int Univ, Dept Phys, 11200 SW 8th St, Miami, FL 33199 USA..
    Veltz, L.
    Univ Paris XI, CNRS, Inst Astrophys Spatiale, UMR 8617, Batiment 121, F-91405 Orsay, France.;Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany..
    Virtanen, J.
    Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland.;Finnish Geospatial Res Inst FGI, Geodeetinrinne 2, Masala 02430, Finland..
    Wallut, J. -M
    Wichmann, R.
    Hamburger Sternwarte, Gojenbergsweg 112, D-21029 Hamburg, Germany..
    Wilkinson, M. I.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England.;Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Ziaeepour, H.
    Univ Bourgogne Franche Comte, OSU THETA Franche Comte Bourgogne, CNRS, Inst UTINAM UMR6213, F-25000 Besancon, France..
    Zschocke, S.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Gaia Data Release 1 Summary of the astrometric, photometric, and survey properties2016In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 595, article id A2Article in journal (Refereed)
    Abstract [en]

    Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illustrations of the scientific quality of the data, followed by a discussion of the limitations due to the preliminary nature of this release. Methods. The raw data collected by Gaia during the first 14 months of the mission have been processed by the Gaia Data Processing and Analysis Consortium (DPAC) and turned into an astrometric and photometric catalogue. Results. Gaia DR1 consists of three components: a primary astrometric data set which contains the positions, parallaxes, and mean proper motions for about 2 million of the brightest stars in common with the HIPPARCOS and Tycho-2 catalogues - a realisation of the Tycho-Gaia Astrometric Solution (TGAS) - and a secondary astrometric data set containing the positions for an additional 1.1 billion sources. The second component is the photometric data set, consisting of mean G-band magnitudes for all sources. The G-band light curves and the characteristics of similar to 3000 Cepheid and RR Lyrae stars, observed at high cadence around the south ecliptic pole, form the third component. For the primary astrometric data set the typical uncertainty is about 0.3 mas for the positions and parallaxes, and about 1 mas yr(-1) for the proper motions. A systematic component of similar to 0.3 mas should be added to the parallax uncertainties. For the subset of similar to 94 000 HIPPARCOS stars in the primary data set, the proper motions are much more precise at about 0.06 mas yr(-1). For the secondary astrometric data set, the typical uncertainty of the positions is similar to 10 mas. The median uncertainties on the mean G-band magnitudes range from the mmag level to similar to 0.03 mag over the magnitude range 5 to 20.7. Conclusions. Gaia DR1 is an important milestone ahead of the next Gaia data release, which will feature five-parameter astrometry for all sources. Extensive validation shows that Gaia DR1 represents a major advance in the mapping of the heavens and the availability of basic stellar data that underpin observational astrophysics. Nevertheless, the very preliminary nature of this first Gaia data release does lead to a number of important limitations to the data quality which should be carefully considered before drawing conclusions from the data.

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    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Ripepi, V.
    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
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    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
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    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
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    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy.;Univ Bologna, Dipartimento Fis & Astron, Via Piero Gobetti 93-2, I-40129 Bologna, Italy..
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    UNED, Dpto Inteligencia Artificial, C Juan Rosal 16, Madrid 28040, Spain..
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    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
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    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Molinaro, R.
    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    Rimoldini, L.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Szabados, L.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklosut 15-17, H-1121 Budapest, Hungary..
    Musella, I.
    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
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    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland.;Johns Hopkins Univ, Dept Phys & Astron, 3400 N Charles St, Baltimore, MD 21218 USA..
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    European Space Res & Technol Ctr ESA ESTEC, Sci Support Off, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    de Bruijne, J. H. J.
    European Space Res & Technol Ctr ESA ESTEC, Sci Support Off, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
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    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
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    INAF, Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Babusiaux, C.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Bailer-Jones, C. A. L.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Bastian, U.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Biermann, M.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Evans, D. W.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Jansen, F.
    European Space Res & Technol Ctr ESA ESTEC, Mission Operat Div, Operat Dept, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Jordi, C.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Klioner, S. A.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Lammers, U.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Lindegren, L.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Mignard, F.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Panem, C.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Pourbaix, D.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium.;FRS FNRS, Rue Egmont 5, B-1000 Brussels, Belgium..
    Randich, S.
    INAF, Osservatorio Astrofis Arcetri, Largo Enrico Fermi 5, I-50125 Florence, Italy..
    Sartoretti, P.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Siddiqui, H. I.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Soubiran, C.
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France..
    Valette, V.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    van Leeuwen, F.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Walton, N. A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Aerts, C.
    Arenou, F.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Cropper, M.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Drimmel, R.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Hog, E.
    Univ Copenhagen, Niels Bohr Inst, Juliane Manes Vej 30, DK-2100 Copenhagen, Denmark..
    Katz, D.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Lattanzi, M. G.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    O'Mullane, W.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Grebel, E. K.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Holland, A. D.
    Open Univ, Dept Phys Sci, Ctr Elect Imaging, Walton Hall, Milton Keynes MK7 6AA, Bucks, England..
    Huc, C.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Passot, X.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Perryman, M.
    European Space Res & Technol Ctr ESA ESTEC, Sci Support Off, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Bramante, L.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Cacciari, C.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Castaneda, J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Chaoul, L.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Cheek, N.
    Serco Gestion Negocios, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    De Angeli, F.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Fabricius, C.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Guerra, R.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Hernandez, J.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Jean-Antoine-Piccolo, A.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Masana, E.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Messineo, R.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Mowlavi, N.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Nienartowicz, K.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Ordonez-Blanco, D.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Panuzzo, P.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Portell, J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Richards, P. J.
    STFC, Rutherford Appleton Lab, Didcot, Oxon, England..
    Riello, M.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Seabroke, G. M.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Tanga, P.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Thevenin, F.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Torra, J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Els, S. G.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany.;ESAC, Gaia DPAC Project Off, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Gracia-Abril, G.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain.;ESAC, Gaia DPAC Project Off, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Comoretto, G.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Garcia-Reinaldos, M.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Lock, T.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Mercier, E.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany.;ESAC, Gaia DPAC Project Off, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Altmann, M.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany.;UPMC, CNRS, Univ Paris 06, SYRTE,Observ Paris,PSL Res Univ,Sorbonne Univ, 61 Ave Observ, F-75014 Paris, France..
    Andrae, R.
    Astraatmadja, T. L.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Bellas-Velidis, I.
    Natl Observ Athens, Athens 15236, Greece..
    Benson, K.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Berthier, J.
    UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Blomme, R.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Busso, G.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Carry, B.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France.;UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Cellino, A.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Cowell, S.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Creevey, O.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France.;Univ Paris XI, CNRS, Inst Astrophys Spatiale, UMR 8617, Batiment 121, F-91405 Orsay, France..
    Cuypers, J.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Davidson, M.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    De Ridder, J.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium..
    de Torres, A.
    ESA ESAC, HE Space Operat BV, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Delchambre, L.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Dell'Oro, A.
    INAF, Osservatorio Astrofis Arcetri, Largo Enrico Fermi 5, I-50125 Florence, Italy..
    Ducourant, C.
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France..
    Fremat, Y.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Garcia-Torres, M.
    Univ Pablo Olavide, Area Lenguajes & Sistemas Informat, Ctra Utrera,Km 1, Seville 141013, Spain..
    Gosset, E.
    FRS FNRS, Rue Egmont 5, B-1000 Brussels, Belgium.;Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Halbwachs, J. -L
    Hambly, N. C.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Harrison, D. L.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England.;Univ Cambridge, Kavli Inst Cosmol, Madingley Rd, Cambride CB3 OHA, England..
    Hauser, M.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Hestroffer, D.
    UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Hodgkin, S. T.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Huckle, H. E.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Hutton, A.
    ESA ESAC, Aurora Technol, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Jasniewicz, G.
    Univ Montpellier, Lab Univers & Particules Montpellier, Pl Eugene Bataillon CC72, F-34095 Montpellier 05, France..
    Jordan, S.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Kontizas, M.
    Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Korn, Anders J.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Lanzafame, A. C.
    Univ Catania, Dipartimento Fis & Astron, Sezione Astrofis, Via S Sofia 78, I-95123 Catania, Italy.;INAF, Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Manteiga, M.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Moitinho, A.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Muinonen, K.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland.;Finnish Geospatial Res Inst FGI, Geodeetinrinne 2, Masala 02430, Finland..
    Osinde, J.
    Isdefe, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Pancino, E.
    INAF, Osservatorio Astrofis Arcetri, Largo Enrico Fermi 5, I-50125 Florence, Italy.;ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy..
    Pauwels, T.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Petit, J. -M
    Recio-Blanco, A.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Robin, A. C.
    Univ Bourgogne Franche Comte, CNRS, Inst UTINAM UMR6213, OSU THETA Franche Comte Bourgogne, F-25000 Besancon, France..
    Siopis, C.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium..
    Smith, M.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Smith, K. W.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Sozzetti, A.
    Thuillot, W.
    UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    van Reeven, W.
    ESA ESAC, Aurora Technol, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Viala, Y.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Abbas, U.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Abreu Aramburu, A.
    Elecnor Deimos Space, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Accart, S.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Aguado, J. J.
    UNED, Dpto Inteligencia Artificial, C Juan Rosal 16, Madrid 28040, Spain..
    Allan, P. M.
    STFC, Rutherford Appleton Lab, Didcot, Oxon, England..
    Allasia, W.
    EURIX Srl, Via Carcano 26, I-10153 Turin, Italy..
    Altavilla, G.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Alvarez, M. A.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Alves, J.
    Univ Vienna, Dept Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria..
    Andrei, A. H.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany.;UPMC, CNRS, Univ Paris 06, SYRTE,Observ Paris,PSL Res Univ,Sorbonne Univ, 61 Ave Observ, F-75014 Paris, France.;ON MCTI BR, Rua Gal Jose Cristino 77, BR-20921400 Rio De Janeiro, RJ, Brazil.;OV UFRJ BR, Ladeira Pedro Antonio 43, BR-20080090 Rio De Janeiro, RJ, Brazil..
    Anglada Varela, E.
    Serco Gestion Negocios, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain.;Isdefe, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Antiche, E.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Antojal, T.
    European Space Res & Technol Ctr ESA ESTEC, Sci Support Off, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Anton, S.
    Univ Porto, Dept Matemat Aplicada, Fac Ciencias, Rua Campo Alegre 687, P-4169007 Oporto, Portugal.;Univ Nova, Inst Astrofis & Ciencias Espaco, Fac Ciencias, P-PT1749016 Lisbon, Portugal..
    Arcay, B.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Bach, N.
    ESA ESAC, Aurora Technol, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Baker, S. G.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Balaguer-Nunez, L.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Barache, C.
    UPMC, CNRS, Univ Paris 06, SYRTE,Observ Paris,PSL Res Univ,Sorbonne Univ, 61 Ave Observ, F-75014 Paris, France..
    Barata, C.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Barbier, A.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Barblan, F.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Barrado y Navascues, D.
    Ctr Astrobiol, Dept Astrofis, CSIC INTA, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Barros, M.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Barstow, M. A.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Becciani, U.
    INAF, Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Bellazzini, M.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Bello Garcia, A.
    Univ Oviedo, Campus Univ, Gijon 33203, Spain..
    Belokurov, V.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Bendjoya, P.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Berihuete, A.
    Univ Cadiz, Avd Univ, Cadiz 11002, Spain..
    Bianchi, L.
    EURIX Srl, Via Carcano 26, I-10153 Turin, Italy..
    Bienayme, O.
    Univ Strasbourg, CNRS, Observ Astronom Strasbourg, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France..
    Billebaud, F.
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France..
    Blagorodnova, N.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Blanco-Cuaresma, S.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland.;Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France..
    Boch, T.
    Univ Strasbourg, CNRS, Observ Astronom Strasbourg, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France..
    Bombrun, A.
    ESA ESAC, HE Space Operat BV, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Borrachero, R.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Bouquillon, S.
    UPMC, CNRS, Univ Paris 06, SYRTE,Observ Paris,PSL Res Univ,Sorbonne Univ, 61 Ave Observ, F-75014 Paris, France..
    Bourda, G.
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France..
    Bragaglia, A.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Breddels, M. A.
    Univ Groningen, Kapteyn Astron Inst, Landleven 12, NL-9747 AD Groningen, Netherlands..
    Brouillet, N.
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France..
    Bruesemeister, T.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Bucciarelli, B.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Burgess, P.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Burgon, R.
    Open Univ, Dept Phys Sci, Ctr Elect Imaging, Walton Hall, Milton Keynes MK7 6AA, Bucks, England..
    Burlacu, A.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Busonero, D.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Buzzi, R.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Caffau, E.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Cambras, J.
    Univ Catalunya, Consorci Serv, C Gran Capita,2-4 3rd floor, Barcelona 08034, Spain..
    Campbell, H.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Cancelliere, R.
    Univ Turin, Dept Comp Sci, Corso Svizzera 185, I-10149 Turin, Italy..
    Cantat-Gaudin, T.
    INAF, Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Carlucci, T.
    UPMC, CNRS, Univ Paris 06, SYRTE,Observ Paris,PSL Res Univ,Sorbonne Univ, 61 Ave Observ, F-75014 Paris, France..
    Carrasco, J. M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Castellani, M.
    INAF, Osservatorio Astron Roma, Via Frascati 33, I-00078 Rome, Italy..
    Charlot, P.
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France..
    Charnas, J.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Chiavassa, A.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Clotet, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Cocozza, G.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Collins, R. S.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Costigan, G.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Crifo, F.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Cross, N. J. G.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Crosta, M.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Crowley, C.
    ESA ESAC, HE Space Operat BV, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Dafonte, C.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Damerdji, Y.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium.;CRAAG, Route Observ BP 63 Bouzareah, Algiers 16340, Algeria..
    Dapergolas, A.
    Natl Observ Athens, Athens 15236, Greece..
    David, P.
    UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    David, M.
    Univ Antwerp, Onderzoeksgroep Toegepaste Wiskunde, Middelheimlaan 1, B-2020 Antwerp, Belgium..
    De Cat, P.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    de Felice, F.
    Univ Padua, Dept Phys & Astron, Via Marzolo 8, I-35131 Padua, Italy..
    de Laverny, P.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    De Luise, F.
    INAF, Osservatorio Astron Teramo, Via Mentore Maggini, I-64100 Teramo, Italy..
    De March, R.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    de Souza, R.
    Univ Sao Paulo, Inst Astron, Geofis & Ciencias Atmosfer, Rua Matao 1226,Cidade Univ, BR-05508900 Sao Paulo, SP, Brazil..
    Debosscher, J.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium..
    del Pozo, E.
    ESA ESAC, Aurora Technol, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Delbo, M.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Delgado, A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Delgado, H. E.
    UNED, Dpto Inteligencia Artificial, C Juan Rosal 16, Madrid 28040, Spain..
    Di Matteo, P.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Diakite, S.
    Univ Bourgogne Franche Comte, CNRS, Inst UTINAM UMR6213, OSU THETA Franche Comte Bourgogne, F-25000 Besancon, France..
    Distefano, E.
    INAF, Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Dolding, C.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Dos Anjos, S.
    Univ Sao Paulo, Inst Astron, Geofis & Ciencias Atmosfer, Rua Matao 1226,Cidade Univ, BR-05508900 Sao Paulo, SP, Brazil..
    Drazinos, P.
    Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Duran, J.
    Isdefe, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Dzigan, Y.
    Tel Aviv Univ, Dept Geosci, IL-6997801 Tel Aviv, Israel.;Univ Amsterdam, Astron Inst Anton Pannekoek, POB 94249, NL-1090 GE Amsterdam, Netherlands..
    Edvardsson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Enke, H.
    Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    Evans, N. W.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Bontemps, G. Eynard
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Fabre, C.
    Ctr Spatial Toulouse, ATOS, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Fabrizio, M.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy.;INAF, Osservatorio Astron Teramo, Via Mentore Maggini, I-64100 Teramo, Italy..
    Falcao, A. J.
    UNINOVA CTS, Campus FCT UNL, P-2829516 Caparica, Portugal..
    Farras Casas, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Federici, L.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Fedorets, G.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland..
    Fernandez-Hernandez, J.
    Serco Gestion Negocios, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain.;UNINOVA CTS, Campus FCT UNL, P-2829516 Caparica, Portugal..
    Fernique, P.
    Univ Strasbourg, CNRS, Observ Astronom Strasbourg, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France..
    Fienga, A.
    Univ Nice Sophia Antipolis, CNRS, Lab Geoazur, UMR 7329,Observ Cote Azur, 250 Rue A Einstein, F-06560 Valbonne, France..
    Figueras, F.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Filippi, F.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Findeisen, K.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Fonti, A.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Fouesneau, M.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Fraile, E.
    ESA ESAC, RHEA, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Fraser, M.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Fuchs, J.
    Acad Sci Czech Republ, Astron Inst, Fricova 298, Ondiejov 25165, Czech Republic..
    Gai, M.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Galleti, S.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Galluccio, L.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Garabato, D.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Garcia-Sedano, F.
    UNED, Dpto Inteligencia Artificial, C Juan Rosal 16, Madrid 28040, Spain..
    Garralda, N.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Gavras, P.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;Natl Observ Athens, Athens 15236, Greece.;Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Gerssen, J.
    Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    Geyer, R.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Gilmore, G.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Girona, S.
    Barcelona Supercomp Ctr, Ctr Nacl Super Computac, C Jordi Girona 29,Ed Nexus 2, Barcelona 08034, Spain..
    Giuffrida, G.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy..
    Gomes, M.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Gonzalez-Marcos, A.
    Univ La Rioja, Dept Mech Engn, C San Jose Calasanz 31, La Rioja 26004, Spain..
    Gonzalez-Nunez, J.
    Serco Gestion Negocios, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain.;Univ Vigo, ETSE Telecomunicac, Campus Lagoas Marcosende, Vigo 36310, Spain..
    Gonzalez-Vidal, J. J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Granvik, M.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland..
    Guerrier, A.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Guillout, P.
    Univ Strasbourg, CNRS, Observ Astronom Strasbourg, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France..
    Guiraud, J.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Gurpide, A.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Gutierrez-Sanchez, R.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Guy, L. P.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Haigron, R.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Hatzidimitriou, D.
    Natl Observ Athens, Athens 15236, Greece.;Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Haywood, M.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Heiter, Ulrike
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Helmi, A.
    Univ Groningen, Kapteyn Astron Inst, Landleven 12, NL-9747 AD Groningen, Netherlands..
    Hobbs, D.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Hofmann, W.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Holl, B.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Holland, G.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Hunt, J. A. S.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Hypki, A.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Icardi, V.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Irwin, M.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    de Fombelle, G. Jevardat
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Jofre, P.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England.;Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France..
    Jonker, P. G.
    Radboud Univ Nijmegen, Dept Astrophys, IMAPP, POB 9010, NL-6500 GL Nijmegen, Netherlands.;SRON Netherlands Inst Space Res, SRON, Sorbonnelaan 2, NL-3584 CA Utrecht, Netherlands..
    Jorissen, A.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium..
    Julbe, F.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Karampelas, A.
    Natl Observ Athens, Athens 15236, Greece.;Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Kochoska, A.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia..
    Kohley, R.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Kolenberg, K.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium.;Univ Antwerp, Phys Dept, Groenenborgerlaan 171, B-2020 Antwerp, Belgium.;Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA..
    Kontizas, E.
    Natl Observ Athens, Athens 15236, Greece..
    Koposov, S. E.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Kordopatis, G.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France.;Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    Koubsky, P.
    Acad Sci Czech Republ, Astron Inst, Fricova 298, Ondiejov 25165, Czech Republic..
    Krone-Martins, A.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Kudryashova, M.
    UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Bachchan, R. K.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Lacoste-Seris, F.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Lanza, A. F.
    INAF, Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Lavigne, J. -B
    Le Poncin-Lafitte, C.
    UPMC, CNRS, Univ Paris 06, SYRTE,Observ Paris,PSL Res Univ,Sorbonne Univ, 61 Ave Observ, F-75014 Paris, France..
    Lebreton, Y.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;Univ Rennes 1, Inst Phys Rennes, F-35042 Rennes, France..
    Lebzelter, T.
    Univ Vienna, Dept Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria..
    Leccia, S.
    INAF, Osservatorio Astron Capodimonte, Via Moiariello 16, I-80131 Naples, Italy..
    Leclerc, N.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Lecoeur-Taibi, I.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Lemaitre, V.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Lenhardt, H.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Leroux, F.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Liao, S.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy.;Chinese Acad Sci, Shanghai Astron Observ, 80 Nandan Rd, Shanghai 200030, Peoples R China..
    Licata, E.
    EURIX Srl, Via Carcano 26, I-10153 Turin, Italy..
    Lindstrom, H. E. P.
    Univ Copenhagen, Niels Bohr Inst, Juliane Manes Vej 30, DK-2100 Copenhagen, Denmark.;CSC Danmark A S, Retortvej 8, DK-2500 Valby, Denmark..
    Lister, T. A.
    Las Cumbres Observ, Global Telescope Network Inc, 6740 Cortona Dr,Suite 102, Goleta, CA 93117 USA..
    Livanou, E.
    Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Lobel, A.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Loeffler, W.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Lopez, M.
    Ctr Astrobiol, Dept Astrofis, CSIC INTA, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Lorenz, D.
    Univ Vienna, Dept Astrophys, Turkenschanzstr 17, A-1180 Vienna, Austria..
    MacDonald, I.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Magalhaes Fernandes, T.
    Managau, S.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Mann, R. G.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Mantelet, G.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Marchal, O.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Marchant, J. M.
    Liverpool John Moores Univ, Astrophys Res Inst, Liverpool L3 5RF, Merseyside, England..
    Marinoni, S.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy.;INAF, Osservatorio Astron Roma, Via Frascati 33, I-00078 Rome, Italy..
    Marrese, P. M.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy.;INAF, Osservatorio Astron Roma, Via Frascati 33, I-00078 Rome, Italy..
    Marschalko, G.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklosut 15-17, H-1121 Budapest, Hungary.;Univ Szeged, Baja Observ, Szegedi 3-70, H-6500 Baja, Hungary..
    Marsha, D. J.
    Univ Paris Diderot, CEA Saclay, Serv Astrophys, Lab AIM,IRFU,CEA DSM,CNRS,Bat 709, F-91191 Gif Sur Yvette, France..
    Martin-Fleitas, J. M.
    ESA ESAC, Aurora Technol, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Martino, M.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Mary, N.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Matijevic, G.
    Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    McMillan, P. J.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Messina, S.
    INAF, Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Michalik, D.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Millar, N. R.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Miranda, B. M. H.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Molina, D.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Molinaro, M.
    INAF, Osservatorio Astron Trieste, Via GB Tiepolo 11, I-34143 Trieste, Italy..
    Molnar, L.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklosut 15-17, H-1121 Budapest, Hungary..
    Monicz, M.
    Univ Paris 11, Univ Paris Saclay, Lab Accelerateur Lineaire, CNRS IN2P3, F-91898 Orsay, France..
    Montegriffo, P.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Mor, R.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Mora, A.
    ESA ESAC, Aurora Technol, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Morbidelli, R.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Morel, T.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Morgenthaler, S.
    Ecole Polytech Fed Lausanne, SB MATHAA STAP, MA B1 473 Batiment MA,Stn 8, CH-1015 Lausanne, Switzerland..
    Morris, D.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Mulone, A. F.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Narbonne, J.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Nelemans, G.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium.;Radboud Univ Nijmegen, Dept Astrophys, IMAPP, POB 9010, NL-6500 GL Nijmegen, Netherlands..
    Nicastro, L.
    INAF, Ist Astrofis Spaziale & Fis Cosm Bologna, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Noval, L.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Ordenovic, C.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Ordieres-Mere, J.
    Tech Univ Madrid, Jose Gutierrez Abascal 2, Madrid 28006, Spain..
    Osborne, P.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Pagani, C.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Pagano, I.
    INAF, Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Pailler, F.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Palacin, H.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Palaversa, L.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Parsons, P.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Pecoraro, M.
    EURIX Srl, Via Carcano 26, I-10153 Turin, Italy..
    Pedrosa, R.
    Ctr Spatial Toulouse, EQUERT Int, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Pentikainen, H.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland..
    Pichon, B.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Piersimoni, A. M.
    INAF, Osservatorio Astron Teramo, Via Mentore Maggini, I-64100 Teramo, Italy..
    Pineau, F. -X
    Plachy, E.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklosut 15-17, H-1121 Budapest, Hungary..
    Plum, G.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Poujoulet, E.
    Ctr Spatial Toulouse, AKKA, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Prsa, A.
    Villanova Univ, Dept Astrophys & Planetary Sci, 800 E Lancaster Ave, Villanova, PA 19085 USA..
    Pulone, L.
    INAF, Osservatorio Astron Roma, Via Frascati 33, I-00078 Rome, Italy..
    Ragaini, S.
    INAF, Osservatorio Astron Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Rago, S.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Rambaux, N.
    UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Ramos-Lerate, M.
    Vitrociset Belgium, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Ranalli, P.
    Lund Univ, Dept Astron & Theoret Phys, Lund Observ, Box 43, S-22100 Lund, Sweden..
    Rauw, G.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Read, A.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Regibo, S.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium..
    Reyle, C.
    Univ Bourgogne Franche Comte, CNRS, Inst UTINAM UMR6213, OSU THETA Franche Comte Bourgogne, F-25000 Besancon, France..
    Ribeiro, R. A.
    UNINOVA CTS, Campus FCT UNL, P-2829516 Caparica, Portugal..
    Riva, A.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Rixon, G.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Roelens, M.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Romero-Gomez, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Rowell, N.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Royer, F.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Ruiz-Dern, L.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Sadowski, G.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium..
    Selles, T. Sagrista
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Sahlmann, J.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Salgado, J.
    Isdefe, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Salguero, E.
    Isdefe, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Sarasso, M.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Savietto, H.
    Fork Res, Rua Cruzado Osberno,Lt 1,9 Esq, Lisbon, Portugal..
    Schultheis, M.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Sciacca, E.
    INAF, Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Segol, M.
    APAVE SUDEUROPE SAS, Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Segovia, J. C.
    Serco Gestion Negocios, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Segransan, D.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Shih, I-C
    Smareglia, R.
    INAF, Osservatorio Astron Trieste, Via GB Tiepolo 11, I-34143 Trieste, Italy..
    Smart, R. L.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Solano, E.
    Ctr Astrobiol, Dept Astrofis, CSIC INTA, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain.;Spanish Virtual Observ, San Cristobal la Laguna, Spain..
    Solitro, F.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Sordo, R.
    INAF, Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Soria Nieto, S.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Souchay, J.
    UPMC, CNRS, Univ Paris 06, SYRTE,Observ Paris,PSL Res Univ,Sorbonne Univ, 61 Ave Observ, F-75014 Paris, France..
    Spagna, A.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Spoto, F.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Stampa, U.
    Heidelberg Univ, Astron Rech Inst, Zentrum Astron, Monchhofstr 12-14, D-69120 Heidelberg, Germany..
    Steele, I. A.
    Liverpool John Moores Univ, Astrophys Res Inst, Liverpool L3 5RF, Merseyside, England..
    Steidelmueller, H.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Stephenson, C. A.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Stoev, H.
    INAF, Fdn Galileo Galilei, Rambla Jose Ana Fernandez Perez 7, Brefia Baja 38712, Santa Cruz Tene, Spain..
    Suess, F. F.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Suveges, M.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Surdej, J.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Szegedi-Elek, E.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklosut 15-17, H-1121 Budapest, Hungary..
    Tapiador, D.
    ESA ESAC, INSA, Camino Bajo Castillo S-N, Madrid 28692, Spain.;Univ Complutense Madrid, Dpto Arquitectura Comp & Automat, Fac Informat, C-Prof Jose Garcia Santesmases S-N, Madrid 28040, Spain..
    Taris, F.
    Tauran, G.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Taylor, M. B.
    Univ Bristol, HH Wills Phys Lab, Tyndall Ave, Bristol BS8 1TL, Avon, England..
    Teixeira, R.
    Univ Sao Paulo, Inst Astron, Geofis & Ciencias Atmosfer, Rua Matao 1226,Cidade Univ, BR-05508900 Sao Paulo, SP, Brazil..
    Terrett, D.
    STFC, Rutherford Appleton Lab, Didcot, Oxon, England..
    Tingley, B.
    Aarhus Univ, Dept Phys & Astron, Stellar Astrophys Ctr, 120 Ny Munkegade,Bldg 1520, DK-8000 Aarhus, Denmark..
    Trager, S. C.
    Univ Groningen, Kapteyn Astron Inst, Landleven 12, NL-9747 AD Groningen, Netherlands..
    Turon, C.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Ulla, A.
    Univ Vigo, Appl Phys Dept, Vigo 36310, Spain..
    Utrilla, E.
    ESA ESAC, Aurora Technol, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Valentini, G.
    INAF, Osservatorio Astron Teramo, Via Mentore Maggini, I-64100 Teramo, Italy..
    van Elteren, A.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Van Hemelryck, E.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    van Leeuwen, M.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Varadi, M.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland.;Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklosut 15-17, H-1121 Budapest, Hungary..
    Vecchiato, A.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Veljanoski, J.
    Univ Groningen, Kapteyn Astron Inst, Landleven 12, NL-9747 AD Groningen, Netherlands..
    Via, T.
    Univ Catalunya, Consorci Serv, C Gran Capita,2-4 3rd floor, Barcelona 08034, Spain..
    Vicente, D.
    Barcelona Supercomp Ctr, Ctr Nacl Super Computac, C Jordi Girona 29,Ed Nexus 2, Barcelona 08034, Spain..
    Vogt, S.
    HE Space Operat BV, ESA ESTEC, Keplerlaan 1, NL-2201AZ Noordwijk, Netherlands..
    Voss, H.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Votruba, V.
    Acad Sci Czech Republ, Astron Inst, Fricova 298, Ondiejov 25165, Czech Republic..
    Voutsinas, S.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Walmsley, G.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Weiler, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Weingrill, K.
    Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    Wevers, T.
    Radboud Univ Nijmegen, Dept Astrophys, IMAPP, POB 9010, NL-6500 GL Nijmegen, Netherlands..
    Wyrzykowski, L.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England.;Univ Warsaw Observ, Al Ujazdowskie 4, PL-00478 Warsaw, Poland..
    Yoldas, A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Zerjal, M.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia..
    Zucker, S.
    Tel Aviv Univ, Dept Geosci, IL-6997801 Tel Aviv, Israel..
    Zurbach, C.
    Univ Montpellier, Lab Univers & Particules Montpellier, Pl Eugene Bataillon CC72, F-34095 Montpellier 05, France..
    Zwitter, T.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia..
    Alecu, A.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Allen, M.
    European Space Res & Technol Ctr ESA ESTEC, Sci Support Off, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Allende Prieto, C.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.;Inst Astrofis Canarias, San Cristobal la Laguna 38205, Tenerife, Spain.;Univ La Laguna, Dept Astrofis, San Cristobal la Laguna 38206, Tenerife, Spain..
    Amorim, A.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Anglada-Escude, G.
    Arsenijevic, V.
    Univ Lisbon, CENTRA, FCUL, Edif C8, P-1749016 Lisbon, Portugal..
    Azaz, S.
    European Space Res & Technol Ctr ESA ESTEC, Sci Support Off, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Balm, P.
    Telespazio Vega UK Ltd, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Beck, M.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Bernsteint, H. -H
    Bigot, L.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Bijaoui, A.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Blasco, C.
    ESA, ESTEC, RHEA, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Bonfigli, M.
    INAF, Osservatorio Astron Teramo, Via Mentore Maggini, I-64100 Teramo, Italy..
    Bono, G.
    INAF, Osservatorio Astron Roma, Via Frascati 33, I-00078 Rome, Italy..
    Boudreault, S.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.;Max Planck Inst Solar Syst Res, Justus Von Liebig Weg 3, D-37077 Gottingen, Germany..
    Bressan, A.
    SISSA, Via Bonomea 265, I-34136 Trieste, Italy..
    Brown, S.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Brunet, P. -M
    Bunclark, P.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Buonanno, R.
    INAF, Osservatorio Astron Roma, Via Frascati 33, I-00078 Rome, Italy..
    Butkevich, A. G.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Carret, C.
    Ctr Spatial Toulouse, EQUERT Int, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Carrion, C.
    UNED, Dpto Inteligencia Artificial, C Juan Rosal 16, Madrid 28040, Spain..
    Chemin, L.
    Univ Bordeaux, CNRS, Lab Astrophys Bordeaux, B18N, F-33615 Pessac, France.;Inst Nacl Pesquisas Espaciais, Minist Ciencia Tecnol, Ave Astronautas 1758, BR-12227010 Sao Jose Dos Campos, SP, Brazil..
    Chereau, F.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Corcione, L.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Darmigny, E.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    de Boer, K. S.
    Univ Bonn, Argelander Inst Astron, Hugel 71, D-53121 Bonn, Germany..
    de Teodoro, P.
    Serco Gestion Negocios, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    de Zeeuw, P. T.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands.;ESO, Karl Schwarzschild Str 2, D-85748 Garching, Germany..
    Delle Luche, C.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Domingues, C. D.
    Univ Lisbon, Fac Sci, Lab Opt Lasers & Syst, Estr Paco Lumiar 22, P-1649038 Lisbon, Portugal..
    Dubath, P.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Fodor, F.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Frezouls, B.
    Ctr Spatial Toulouse, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Fries, A.
    Fustes, D.
    Univ A Coruna, Fac Informat, Campus Elvina S-N, La Coruna 15071, Spain..
    Fyfe, D.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Gallardo, E.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Gallegos, J.
    Serco Gestion Negocios, ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Gardiol, D.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Gebran, M.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain.;Notre Dame Univ, Dept Phys & Astron, POB 72, Zouk Mikael, Lebanon..
    Gomboc, A.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia.;Univ Nova Gorica, Vipayska 13, Nova Gorica 5000, Slovenia..
    Gomez, A.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Grux, E.
    Univ Bourgogne Franche Comte, CNRS, Inst UTINAM UMR6213, OSU THETA Franche Comte Bourgogne, F-25000 Besancon, France..
    Gueguen, A.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;Max Planck Inst Extraterr Phys, OPINAS, Giessenbachstr, D-85741 Garching, Germany..
    Heyrovsky, A.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Hoar, J.
    European Space Astron Ctr ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Iannicola, G.
    INAF, Osservatorio Astron Roma, Via Frascati 33, I-00078 Rome, Italy..
    Parache, Y. Isasi
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Janotto, A. -M
    Joliet, E.
    ESA ESAC, HE Space Operat BV, Camino Bajo Castillo S-N, Madrid 28692, Spain.;CALTECH, NASA IPAC Infrared Sci Arch, Mail Code 100-22,770 South Wilson Ave, Pasadena, CA 91125 USA..
    Jonckheere, A.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Keil, R.
    Univ Bremen, Ctr Appl Space Technol & Micrograv ZARM, Am Fallturm 1, D-28359 Bremen, Germany.;ESA, ESOC, RHEA Syst, Robert Bosch Str 5, D-64293 Darmstadt, Germany..
    Kim, D. -W
    Klagyivik, P.
    Hungarian Acad Sci, Res Ctr Astron & Earth Sci, Konkoly Observ, Konkoly Thege Miklosut 15-17, H-1121 Budapest, Hungary..
    Klar, J.
    Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    Knude, J.
    Univ Copenhagen, Niels Bohr Inst, Juliane Manes Vej 30, DK-2100 Copenhagen, Denmark..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Kolka, I.
    Tartu Observ, EE-61602 Toravere, Estonia..
    Kos, J.
    Univ Ljubljana, Fac Math & Phys, Jadranska Ulica 19, Ljubljana 1000, Slovenia.;Univ Sydney, Sch Phys A28, Sydney Inst Astron, Sydney, NSW 2006, Australia..
    Kutka, A.
    Acad Sci Czech Republ, Astron Inst, Fricova 298, Ondiejov 25165, Czech Republic.;Slovak Org Space Activ, Zamocka 18, Bratislava 85101, Slovakia..
    Lainey, V.
    UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    LeBouquin, D.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Liu, C.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany.;Chinese Acad Sci, Natl Astron Observ, Beijing 100012, Peoples R China..
    Loreggia, D.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Makarov, V. V.
    US Naval Observ, Astrometry Dept, 3450 Massachusetts Ave, Washington, DC 20392 USA..
    Marseille, M. G.
    Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Martayan, C.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium.;ESO, Alonso Cordova 3107,Casilla 19001, Santiago, Chile..
    Martinez-Rubi, O.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Massart, B.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France.;Ctr Spatial Toulouse, Thales Serv, CNES, 18 Ave Edouard Belin, F-31401 Toulouse 9, France.;Airbus Def & Space SAS, 31 Rue Cosmonautes, F-31402 Toulouse 4, France..
    Meynadier, F.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France.;UPMC, CNRS, Univ Paris 06, SYRTE,Observ Paris,PSL Res Univ,Sorbonne Univ, 61 Ave Observ, F-75014 Paris, France..
    Mignot, S.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Munari, U.
    INAF, Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Nguyen, A. -T
    Nordlander, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    O'Flaherty, K. S.
    ESA ESTEC, EJR Quartz BV, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Ocvirk, P.
    Univ Strasbourg, CNRS, Observ Astronom Strasbourg, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France.;Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    Olias Sanz, A.
    ESA ESAC, Server Labs, Camino Bajo Castillo S-N, Madrid, Spain..
    Ortiz, P.
    Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Osorio, J.
    Univ Porto, Dept Matemat Aplicada, Fac Ciencias, Rua Campo Alegre 687, P-4169007 Oporto, Portugal..
    Oszkiewicz, D.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland.;Adam Mickiewicz Univ, Fac Phys, Astron Observ Inst, Ul Sloneczna 36, PL-60286 Poznan, Poland..
    Ouzounis, A.
    Univ Edinburgh, Inst Astron, Royal Observ, Blackford Hill, Edinburgh EH9 3HJ, Midlothian, Scotland..
    Park, P.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Pasquato, E.
    Univ Libre Bruxelles, Inst Astron & Astrophys, CP 226,Blvd Triomphe, B-1050 Brussels, Belgium..
    Peltzer, C.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England..
    Peralta, J.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Peturaud, F.
    Univ Paris Diderot, Observ Paris, CNRS, GEPI,PSL Res Univ,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Pieniluoma, T.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland..
    Pigozzi, E.
    ALTEC Spa, Corso Marche 79, I-10146 Turin, Italy..
    Poels, J.
    Univ Liege, Inst Astrophys & Geophys, 19c,Allee 6 Aout, B-4000 Liege, Belgium..
    Prat, G.
    CS Syst Informat CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Prod'homme, T.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands.;European Space Res & Technol Ctr ESA ESTEC, Directorate Sci, Keplerlaan 1, NL-2201 AZ Noordwijk, Netherlands..
    Raison, F.
    Max Planck Inst Extraterr Phys, OPINAS, Giessenbachstr, D-85741 Garching, Germany.;ESA ESAC, Praesepe BV, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Rebordao, J. M.
    Univ Lisbon, Fac Sci, Lab Opt Lasers & Syst, Estr Paco Lumiar 22, P-1649038 Lisbon, Portugal..
    Risquez, D.
    Leiden Univ, Leiden Observ, Niels Bohrweg 2, NL-2333 CA Leiden, Netherlands..
    Rocca-Volmerange, B.
    Sorbonne Univ UPMC, CNRS, UMR7095, Inst Astrophys Paris, F-75014 Paris, France..
    Rosen, S.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England.;Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Ruiz-Fuertes, M. I.
    Univ Geneva, Dept Astron, Chemin Ecogia 16, CH-1290 Versoix, Switzerland..
    Russo, F.
    INAF, Osservatorio Astron Torino, Via Osservatorio 20, I-10025 Pino Torinese, Italy..
    Serraller Vizcaino, I.
    ESA ESAC, GMV, Camino bajo Castillo S-N, Madrid 28692, Spain..
    Short, A.
    Siebert, A.
    Univ Strasbourg, CNRS, Observ Astronom Strasbourg, UMR 7550, 11 Rue Univ, F-67000 Strasbourg, France.;Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    Silva, H.
    UNINOVA CTS, Campus FCT UNL, P-2829516 Caparica, Portugal..
    Sinachopoulos, D.
    Natl Observ Athens, Athens 15236, Greece..
    Slezak, E.
    Univ Nice Sophia Antipolis, Lab Lagrange, Observ Cote Azur, CNRS, CS 34229, F-06304 Nice, France..
    Soffel, M.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Sosnowska, D.
    Univ Geneva, Dept Astron, Chemin Maillettes 51, CH-1290 Versoix, Switzerland..
    Straizys, V.
    Vilnius Univ, Inst Theoret Phys & Astron, Sauletekio 3, LT-10222 Vilnius, Lithuania..
    ter Linden, M.
    ESA ESAC, HE Space Operat BV, Camino Bajo Castillo S-N, Madrid 28692, Spain.;S&T Corp, POB 608, NL-2600 AP Delft, Netherlands..
    Terrell, D.
    Southwest Res Inst SwRI, Dept Space Studies, 1050 Walnut St,Suite 300, Boulder, CO 80302 USA..
    Theil, S.
    Deutsch Zentrum Luft & Raumfahrt, Inst Space Syst, Fallturm 1, D-28359 Bremen, Germany..
    Tiede, C.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany.;Univ Appl Sci Munich, Karlstr 6, D-80333 Munich, Germany..
    Troisi, L.
    ASI Sci Data Ctr, Via Politecn SNC, I-00133 Rome, Italy.;Univ Roma Tor Vergata, Dipartimento Fis, Via Ric Sci 1, I-00133 Rome, Italy..
    Tsalmantza, P.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Tur, D.
    Univ Catalunya, Consorci Serv, C Gran Capita,2-4 3rd floor, Barcelona 08034, Spain..
    Vaccari, M.
    Univ Western Cape, Dept Phys & Astron, Robert Sobukwe Rd, ZA-7535 Cape Town, South Africa.;INAF, Ist Radioastron, Via Piero Gobetti 101, I-40129 Bologna, Italy..
    Vachier, F.
    UPMC, Univ Paris 06, Observ Paris, IMCCE,PSL Res Univ,CNRS,Sorbonne Univ,Univ Lille, 77 Av Denfert Rochereau, F-75014 Paris, France..
    Valles, P.
    Univ Barcelona, Inst Ciencies Cosmos, IEEC UB, Marti Franques 1, Barcelona 08028, Spain..
    Van Hamme, W.
    Florida Int Univ, Dept Phys, 11200 SW 8th St, Miami, FL 33199 USA..
    Veltz, L.
    Univ Paris XI, CNRS, Inst Astrophys Spatiale, UMR 8617, Batiment 121, F-91405 Orsay, France.;Leibniz Inst Astrophys Potsdam AIP, An Der Stern warte 16, D-14482 Potsdam, Germany..
    Virtanen, J.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland.;Finnish Geospatial Res Inst FGI, Geodeetinrinne 2, Masala 02430, Finland..
    Wallut, J. -M
    Wichmann, R.
    Hamburger Sternwarte, Gojenbergsweg 112, D-21029 Hamburg, Germany..
    Wilkinson, M. I.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 OHA, England.;Univ Leicester, Dept Phys & Astron, Univ Rd, Leicester LE1 7RH, Leics, England..
    Ziaeepour, H.
    Univ Bourgogne Franche Comte, CNRS, Inst UTINAM UMR6213, OSU THETA Franche Comte Bourgogne, F-25000 Besancon, France..
    Zschocke, S.
    Tech Univ Dresden, Lohrmann Observ, Mommsenstr 13, D-01062 Dresden, Germany..
    Testing parallaxes with local Cepheids and RR Lyrae stars2017In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 605, article id A79Article in journal (Refereed)
    Abstract [en]

    Context. Parallaxes for 331 classical Cepheids, 31 Type II Cepheids, and 364 RR Lyrae stars in common between Gaia and the HIPPARCOS and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). Aims. In order to test these first parallax measurements of the primary standard candles of the cosmological distance ladder, which involve astrometry collected by Gaia during the initial 14 months of science operation, we compared them with literature estimates and derived new period-luminosity (PL), period-Wesenheit (PW) relations for classical and Type II Cepheids and infrared PL, PL-metallicity (PLZ), and optical luminosity-metallicity (MV-[Fe/H]) relations for the RR Lyrae stars, with zero points based on TGAS.

    Methods. Classical Cepheids were carefully selected in order to discard known or suspected binary systems. The final sample comprises 102 fundamental mode pulsators with periods ranging from 1.68 to 51.66 days (of which 33 with sigma(omega)/omega < 0 : 5). The Type II Cepheids include a total of 26 W Virginis and BL Herculis stars spanning the period range from 1.16 to 30.00 days (of which only 7 with sigma(omega)/omega 0 : 5). The RR Lyrae stars include 200 sources with pulsation period ranging from 0.27 to 0.80 days (of which 112 with sigma(omega)/omega < 0 : 5). The new relations were computed using multi- band (V; I; J; K-s) photometry and spectroscopic metal abundances available in the literature, and by applying three alternative approaches: (i) linear least-squares fitting of the absolute magnitudes inferred from direct transformation of the TGAS parallaxes; (ii) adopting astrometry-based luminosities; and (iii) using a Bayesian fitting approach. The last two methods work in parallax space where parallaxes are used directly, thus maintaining symmetrical errors and allowing negative parallaxes to be used. The TGAS-based PL; PW; PLZ, and MV [Fe/H] relations are discussed by comparing the distance to the Large Magellanic Cloud provided by different types of pulsating stars and alternative fitting methods.

    Results. Good agreement is found from direct comparison of the parallaxes of RR Lyrae stars for which both TGAS and HST measurements are available. Similarly, very good agreement is found between the TGAS values and the parallaxes inferred from the absolute magnitudes of Cepheids and RR Lyrae stars analysed with the Baade-Wesselink method. TGAS values also compare favourably with the parallaxes inferred by theoretical model fitting of the multi-band light curves for two of the three classical Cepheids and one RR Lyrae star, which were analysed with this technique in our samples. The K-band PL relations show the significant improvement of the TGAS parallaxes for Cepheids and RR Lyrae stars with respect to the HIPPARCOS measurements. This is particularly true for the RR Lyrae stars for which improvement in quality and statistics is impressive.

    Conclusions. TGAS parallaxes bring a significant added value to the previous HIPPARCOS estimates. The relations presented in this paper represent the first Gaia-calibrated relations and form a work-in-progress milestone report in the wait for Gaia-only parallaxes of which a first solution will become available with Gaia Data Release 2 (DR2) in 2018.

  • 23.
    Cole, E. M.
    et al.
    Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland..
    Hackman, T.
    Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland.;Univ Turku, Finnish Ctr Astron ESO, Piikkio 21500, Finland..
    Kapyka, M. J.
    Aalto Univ, Dept Comp Sci, ReSoLVE Ctr Excellence, Espoo 00076, Finland..
    Ilyin, I.
    Leibniz Inst Astrophys Potsdam, D-14882 Potsdam, Germany..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Doppler imaging of LQ Hydrae for 1998-20022015In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 581, article id A69Article in journal (Refereed)
    Abstract [en]

    Aims. We study the spot distribution on the surface of LQ Hya during the observing seasons October 1998-November 2002. We look for persistent active longitudes, trends in the level of spot activity and compare to photometric data. Methods. We apply the Doppler imaging technique on photospheric spectral lines using an inversion code to retrieve images of the surface temperature. Results. We present new temperature maps using multiple spectral lines for a total of 7 seasons. Conclusions. We find no evidence for active longitudes persisting over multiple observing seasons. The spot activity appears to be concentrated to two latitude regions. Using the currently accepted rotation period, we find spot structures to show a trend in the phase-time plot, indicative of a need for a longer period. We conclude that the long-term activity of LQ Hya is more chaotic than that of some magnetically active binary stars analyzed with similar methods, but still with clear indications of an activity cycle from the photometry.

  • 24.
    Cole-Kodikara, Elizabeth M.
    et al.
    Leibniz Inst Astrophys Potsdam, Sternwarte 16, D-14482 Potsdam, Germany.
    Kaepylae, Maarit J.
    Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, Gottingen, Germany;Aalto Univ, ReSoLVE Ctr Excellence, Dept Comp Sci, Helsinki, Finland.
    Lehtinen, Jyri J.
    Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, Gottingen, Germany;Aalto Univ, ReSoLVE Ctr Excellence, Dept Comp Sci, Helsinki, Finland.
    Hackman, Thomas
    Univ Helsinki, Dept Phys, POB 64, FIN-00014 Helsinki, Finland.
    Ilyin, Ilya, V
    Leibniz Inst Astrophys Potsdam, Sternwarte 16, D-14482 Potsdam, Germany.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Spot evolution on LQ Hya from 2006-2017: temperature maps based on SOFIN and FIES data2019In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 629, no Sept, article id A120Article in journal (Refereed)
    Abstract [en]

    Context. LQ Hya is one of the most frequently studied young solar analogue stars. Recently, it has been observed to show intriguing behaviour when analysing long-term photometry. For instance, from 2003-2009, a coherent spot structure migrating in the rotational frame was reported by various authors. However, ever since, the star has entered a chaotic state where coherent structures seem to have disappeared and rapid phase jumps of the photometric minima occur irregularly over time. Aims. LQ Hya is one of the stars included in the SOFIN/FIES long-term monitoring campaign extending over 25 yr. Here, we publish new temperature maps for the star during 2006-2017, covering the chaotic state of the star. Methods. We used a Doppler imaging technique to derive surface temperature maps from high-resolution spectra. Results. From the mean temperatures of the Doppler maps, we see a weak but systematic increase in the surface temperature of the star. This is consistent with the simultaneously increasing photometric magnitude. During nearly all observing seasons, we see a high-latitude spot structure which is clearly non-axisymmetric. The phase behaviour of this structure is very chaotic but agrees reasonably well with the photometry. Equatorial spots are also frequently seen, but we interpret many of them to be artefacts due to the poor to moderate phase coverage. Conclusions. Even during the chaotic phase of the star, the spot topology has remained very similar to the higher activity epochs with more coherent and long-lived spot structures. In particular, we see high-latitude and equatorial spot activity, the mid latitude range still being most often void of spots. We interpret the erratic jumps and drifts in phase of the photometric minima to be caused by changes in the high-latitude spot structure rather than the equatorial spots.

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  • 25.
    Creevey, O. L.
    et al.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Sordo, R.
    INAF Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Pailler, F.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Fremat, Y.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Heiter, Ulrike
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Thevenin, F.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Andrae, R.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Fouesneau, M.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Lobel, A.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Bailer-Jones, C. A. L.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Garabato, D.
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Bellas-Velidis, I.
    Natl Observ Athens, 1 Metaxa & Vas Pavlou,Palaia Penteli, Athens 15236, Greece..
    Brugaletta, E.
    INAF Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy..
    Lorca, A.
    Aurora Technol European Space Agcy ESA, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Ordenovic, C.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Palicio, P. A.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Sarro, L. M.
    UNED, Dept Inteligencia Artificial, C Juan Rosal 16, Madrid 28040, Spain..
    Delchambre, L.
    Univ Liege, Inst Astrophys & Geophys, 19C,Allee 6 Aout, B-4000 Liege, Belgium..
    Drimmel, R.
    INAF Osservatorio Astrofis Torino, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Rybizki, J.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Elipe, G. Torralba
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Korn, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Recio-Blanco, A.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Schultheis, M. S.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    De Angeli, F.
    Univ Cambridge, Inst Astron, Madingley Rd, Cambridge CB3 0HA, England..
    Montegri, P.
    INAF Osservatorio Astrofis & Sci Spazio Bologna, Via Piero Gobetti 93-3, I-40129 Bologna, Italy..
    Aramburu, A. Abreu
    ATG Europe European Space Agcy ESA, Camino Bajo Castillo,S-N, Madrid 28692, Spain..
    Accart, S.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Alvarez, M. A.
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Bakker, J.
    European Space Agcy ESA, European Space Astron Ctr ESAC, Camino Bajo Castillo,S-N, Madrid 28692, Spain..
    Brouillet, N.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Burlacu, A.
    Telespazio CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Carballo, R.
    Univ Cantabria, Dept Matemat Aplicada & Ciencias Computac, ETS Ingenieros Caminos Canales & Puertos, Ave Castros S-N, Santander 39005, Spain..
    Casamiquela, L.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France.;Univ PSL, CNRS, GEPI, Observ Paris, 5 Pl Jules Janssen, F-92190 Meudon, France..
    Chiavassa, A.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Contursi, G.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Cooper, W. J.
    INAF Osservatorio Astrofis Torino, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy.;Univ Hertfordshire, Ctr Astrophys Res, Coll Lane, Hatfield AL10 9AB, Herts, England..
    Dafonte, C.
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Dapergolas, A.
    Natl Observ Athens, 1 Metaxa & Vas Pavlou,Palaia Penteli, Athens 15236, Greece..
    de Laverny, P.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Dharmawardena, T. E.
    Max Planck Inst Astron, Konigstuhl 17, D-69117 Heidelberg, Germany..
    Edvardsson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Theoretical Astrophysics. Uppsala Univ, Theoret Astrophys, Div Astron & Space Phys, Dept Phys & Astron, Box 516, S-75120 Uppsala, Sweden..
    Le Fustec, Y.
    Telespazio CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Garcia-Lario, P.
    European Space Agcy ESA, European Space Astron Ctr ESAC, Camino Bajo Castillo,S-N, Madrid 28692, Spain..
    Garcia-Torres, M.
    Univ Pablo de Olavide, Data Sci & Big Data Lab, Seville 41013, Spain..
    Gomez, A.
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Gonzalez-Santamaria, I.
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Hatzidimitriou, D.
    Natl & Kapodistrian Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Piccolo, A. Jean-Antoine
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Kontiza, M.
    Natl & Kapodistrian Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Kordopatis, G.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Lanzafame, A. C.
    INAF Osservatorio Astrofis Catania, Via S Sofia 78, I-95123 Catania, Italy.;Univ Catania, Dipartimento Fis & Astron Ettore Majorana, Via S Sofia 64, I-95123 Catania, Italy..
    Lebreton, Y.
    Univ Paris, Sorbonne Univ, Univ PSL, CNRS,LESIA,Observ Paris, 5 Pl Jules Janssen, F-92190 Meudon, France.;Univ Rennes, CNRS, IPR Inst Phys Rennes, UMR 6251, F-35000 Rennes, France..
    Licata, E. L.
    INAF Osservatorio Astrofis Torino, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Lindstrom, H. E. P.
    INAF Osservatorio Astrofis Torino, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy.;Univ Copenhagen, Niels Bohr Inst, Juliane Maries Vej 30, DK-2100 Copenhagen O, Denmark.;DXC Technol, Retortvej 8, DK-2500 Valby, Denmark..
    Livanou, E.
    Natl & Kapodistrian Univ Athens, Dept Astrophys Astron & Mech, Athens 15783, Greece..
    Romeo, A. Magdaleno
    Telespazio CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Manteiga, M.
    Univ A Coruna, Dept Naut Sci & Marine Engn, CIGUS CITIC, Paseo Ronda 51, La Coruna 15071, Spain..
    Marocco, F.
    CALTECH, IPAC, Mail Code 100-22, Pasadena, CA 10022 USA..
    Marshall, D. J.
    Univ Toulouse, CNRS, IRAP, UPS, 9Ave Colonel Roche,BP 44346, F-31028 Toulouse 4, France..
    Mary, N.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Nicolas, C.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Pallas-Quintela, L.
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Panem, C.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Pichon, B.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Poggio, E.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France.;INAF Osservatorio Astrofis Torino, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Riclet, F.
    CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Robin, C.
    CNES Ctr Spatial Toulouse, Thales Serv, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Santovena, R.
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Silvelo, A.
    Univ A Coruna, CIGUS CITIC, Dept Comp Sci & Informat Technol, Campus Elvina S-N, La Coruna 15071, Spain..
    Slezak, I.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Smart, R. L.
    INAF Osservatorio Astrofis Torino, Via Osservatorio 20, I-10025 Pino Torinese, TO, Italy..
    Soubiran, C.
    Univ Bordeaux, Lab Astrophys Bordeaux, CNRS, B18N,Allee Geoffroy St Hilaire, F-33615 Pessac, France..
    Suveges, M.
    Univ Geneva, Inst Global Hlth, Geneva, Switzerland..
    Ulla, A.
    Univ Vigo, Dept Appl Phys, Vigo 36310, Spain..
    Utrilla, E.
    Aurora Technol European Space Agcy ESA, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Vallenari, A.
    INAF Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Zhao, H.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France..
    Zorec, J.
    Sorbonne Univ, Inst Astrophys Paris, CNRS, UMR7095, 98 Bis Bd Arago, F-75014 Paris, France..
    Barrado, D.
    CSIC, Ctr Astrobiol, INTA, Dept Astrofis,ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Bijaoui, A.
    Univ Cote Azur, Observ Cote Azur, CNRS, Lab Lagrange, Bd Observ,CS 34229, F-06304 Nice 4, France.;CSIC, Ctr Astrobiol, INTA, Dept Astrofis,ESA ESAC, Camino Bajo Castillo S-N, Madrid 28692, Spain..
    Bouret, J. -C
    Blomme, R.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium..
    Brott, I.
    Hamburger Sternwarte, Gojenbergsweg 112, D-21029 Hamburg, Germany..
    Cassisi, S.
    INAF Osservatorio Astron Abruzzo, Via M Maggini,S-N, I-64100 Teramo, Italy.;INFN Sez Pisa, Largo Pontecorvo 3, I-56127 Pisa, Italy..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Martayan, C.
    European Org Astron Res Southern Hemisphere, Alonso Cordova 3107, Santiago 19001, Chile..
    Shulyak, D.
    Georg August Univ, Inst Astrophys, D-37077 Gottingen, Germany.;CSIC, Inst Astrofis Andalucia, Granada 18008, Spain..
    Silvester, J.
    APAVE SUDEUROPE SAS, CNES Ctr Spatial Toulouse, 18 Ave Edouard Belin, F-31401 Toulouse 9, France..
    Gaia Data Release 3: Astrophysical parameters inference system (Apsis). I. Methods and content overview2023In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 674, article id A26Article in journal (Refereed)
    Abstract [en]

    Gaia Data Release 3 contains a wealth of new data products for the community. Astrophysical parameters are a major component of this release, and were produced by the Astrophysical parameters inference system (Apsis) within the Gaia Data Processing and Analysis Consortium (DPAC). The aim of this paper is to describe the overall content of the astrophysical parameters in Gaia DR3 and how they were produced. In Apsis, we use the mean BP /RP and mean RVS spectra along with astrometry and photometry, and we derive the following parameters: source classification and probabilities for 1.6 billion objects; interstellar medium characterisation and distances for up to 470 million sources, including a 2D total Galactic extinction map; 6 million redshifts of quasar candidates; 1.4 million redshifts of galaxy candidates; and an analysis of 50 million outlier sources through an unsupervised classification. The astrophysical parameters also include many stellar spectroscopic and evolutionary parameters for up to 470 million sources. These comprise T-eff, log g, and [M /H] (470 million using BP /RP, 6 million using RVS), radius (470 million), mass (140 million), age (120 million), chemical abundances (up to 5 million), diffuse interstellar band analysis (0.5 million), activity indices (2 million), H ff equivalent widths (200 million), and further classification of spectral types (220 million) and emission-line stars (50 000). This paper is the first in a series of three papers, and focusses on describing the global content of the parameters in Gaia DR3. The accompanying Papers II and III focus on the validation and use of the stellar and non-stellar products, respectively. This catalogue is the most extensive homogeneous database of astrophysical parameters to date, and is based uniquely on Gaia data. It will only be superseded by Gaia Data Release 4, and will therefore remain a key reference over the next four years, providing astrophysical parameters independent of other ground- and space-based data.

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  • 26.
    Cunha, M. S.
    et al.
    Univ Porto, Inst Astrofis & Ciencias Espaco, CAUP, Rua Estrelas, PT-4150762 Porto, Portugal.
    Antoci, V.
    Aarhus Univ, Stellar Astrophys Ctr, Ny Munkegade 120, DK-8000 Aarhus, Denmark.
    Holdsworth, D. L.
    Univ Cent Lancashire, Jeremiah Horrocks Inst, Preston PR1 2HE, Lancs, England.
    Kurtz, D. W.
    Univ Cent Lancashire, Jeremiah Horrocks Inst, Preston PR1 2HE, Lancs, England.
    Balona, L. A.
    South African Astron Observ, POB 9, Cape Town, South Africa.
    Bognar, Zs.
    MTA CSFK, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary;MTA CSFK Lendulet Near Field Cosmol Res Grp, Budapest, Hungary.
    Bowman, D. M.
    Katholieke Univ Leuven, Inst Astron, Celestijnenlaan 200D, B-3001 Leuven, Belgium.
    Guo, Z.
    Penn State Univ, Ctr Exoplanets & Habitable Worlds, 525 Davey Lab, University Pk, PA 16802 USA;Polish Acad Sci, Copernicus Astron Ctr, Bartycka 18, PL-00716 Warsaw, Poland.
    Kolaczek-Szymanski, P. A.
    Univ Wroclaw, Astron Inst, Ul Kopernika 11, PL-51622 Wroclaw, Poland.
    Lares-Martiz, M.
    CSIC, Inst Astrofis Andalucia, Glorieta Astron S-N, E-18008 Granada, Spain.
    Paunzen, E.
    Masaryk Univ, Dept Theoret Phys & Astrophys, Kotlarska 2, CS-61137 Brno, Czech Republic.
    Skarka, M.
    Masaryk Univ, Dept Theoret Phys & Astrophys, Kotlarska 2, CS-61137 Brno, Czech Republic;Czech Acad Sci, Astron Inst, Fricova 298, Ondrejov 25165, Czech Republic.
    Smalley, B.
    Keele Univ, Astrophys Grp, Keele ST5 5BG, Staffs, England.
    Sodor, A.
    MTA CSFK, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary;MTA CSFK Lendulet Near Field Cosmol Res Grp, Budapest, Hungary.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Pepper, J.
    Lehigh Univ, Dept Phys, 16 Mem Dr East, Bethlehem, PA 18015 USA.
    Richey-Yowell, T.
    Arizona State Univ, Sch Earth & Space Explorat, Tempe, AZ 85281 USA.
    Ricker, G. R.
    MIT, Dept Phys, Cambridge, MA 02139 USA;MIT, Kavli Inst Astrophys & Space Res, 77 Massachusetts Ave, Cambridge, MA 02139 USA.
    Seager, S.
    MIT, Dept Phys, Cambridge, MA 02139 USA;MIT, Kavli Inst Astrophys & Space Res, 77 Massachusetts Ave, Cambridge, MA 02139 USA;MIT, Earth & Planetary Sci, 77 Massachusetts Ave, Cambridge, MA 02139 USA.
    Buzasi, D. L.
    Florida Gulf Coast Univ, Dept Chem & Phys, 10501 FGCU Blvd S, Ft Myers, FL 33965 USA.
    Fox-Machado, L.
    Univ Nacl Autonoma Mexico, Inst Astron, Ap P 877, Ensenada 22860, BC, Mexico.
    Hasanzadeh, A.
    Univ Zanjan, Dept Phys, Zanjan, Iran.
    Niemczura, E.
    Univ Wroclaw, Astron Inst, Ul Kopernika 11, PL-51622 Wroclaw, Poland.
    Quitral-Manosalva, P.
    Univ Porto, Inst Astrofis & Ciencias Espaco, CAUP, Rua Estrelas, PT-4150762 Porto, Portugal;Univ Porto, Dept Fis & Astron, Fac Ciencias, Porto, Portugal.
    Monteiro, M. J. P. F. G.
    Univ Porto, Inst Astrofis & Ciencias Espaco, CAUP, Rua Estrelas, PT-4150762 Porto, Portugal;Univ Porto, Dept Fis & Astron, Fac Ciencias, Porto, Portugal.
    Stateva, I.
    Bulgarian Acad Sci, Inst Astron, Blvd Tsarigradsko Chaussee 72, BU-1784 Sofia, Bulgaria;Bulgarian Acad Sci, NAO, Blvd Tsarigradsko Chaussee 72, BU-1784 Sofia, Bulgaria.
    De Cat, P.
    Royal Observ Belgium, Ringlaan 3, B-1180 Brussels, Belgium.
    Garcia Hernandez, A.
    Univ Granada, Dept Fis Teor & Cosmos, Campus Fuentenueva S-N, E-18071 Granada, Spain.
    Ghasemi, H.
    IASBS, Dept Phys, Zanjan 4513766731, Iran.
    Handler, G.
    Polish Acad Sci, Copernicus Astron Ctr, Bartycka 18, PL-00716 Warsaw, Poland.
    Hey, D.
    Aarhus Univ, Stellar Astrophys Ctr, Ny Munkegade 120, DK-8000 Aarhus, Denmark;Univ Sydney, Sydney Inst Astron, Sch Phys, Sydney, NSW 2006, Australia.
    Matthews, J. M.
    Univ British Columbia, Dept Phys & Astron, Vancouver, BC, Canada.
    Nemec, J. M.
    Camosun Coll, Dept Phys & Astron, Victoria, BC, Canada.
    Pascual-Granado, J.
    CSIC, Inst Astrofis Andalucia, Glorieta Astron S-N, E-18008 Granada, Spain.
    Safari, H.
    Univ Zanjan, Dept Phys, Zanjan, Iran.
    Suarez, J. C.
    CSIC, Inst Astrofis Andalucia, Glorieta Astron S-N, E-18008 Granada, Spain;Univ Granada, Dept Fis Teor & Cosmos, Campus Fuentenueva S-N, E-18071 Granada, Spain.
    Szabo, R.
    MTA CSFK, Konkoly Observ, Konkoly Thege Miklos Ut 15-17, H-1121 Budapest, Hungary;MTA CSFK Lendulet Near Field Cosmol Res Grp, Budapest, Hungary.
    Tkachenko, A.
    Katholieke Univ Leuven, Inst Astron, Celestijnenlaan 200D, B-3001 Leuven, Belgium.
    Weiss, W. W.
    Univ Vienna, Dept Astrophys, Tuerkenschanzstr 17, A-1180 Vienna, Austria.
    Rotation and pulsation in Ap stars: first light results from TESS sectors 1 and 22019In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 487, no 3, p. 3523-3549Article in journal (Refereed)
    Abstract [en]

    We present the first results from the Transiting Exoplanet Survey Satellite (TESS) on the rotational and pulsational variability of magnetic chemically peculiar A-type stars. We analyse TESS 2-min cadence data from sectors 1 and 2 on a sample of 83 stars. Five new rapidly oscillating Ap (roAp) stars are announced. One of these pulsates with periods around 4.7 min, making it the shortest period roAp star known to date. Four out of the five new roAp stars are multiperiodic. Three of these and the singly periodic one show the presence of rotational mode splitting. Individual frequencies are provided in all cases. In addition, seven previously known roAp stars are analysed. Additional modes of oscillation are found in some stars, while in others we are able to distinguish the true pulsations from possible aliases present in the ground-based data. We find that the pulsation amplitude in the TESS filter is typically a factor of 6 smaller than that in the B filter, which is usually used for ground-based observations. For four roAp stars we set constraints on the inclination angle and magnetic obliquity, through the application of the oblique pulsator model. We also confirm the absence of roAp-type pulsations down to amplitude limits of 6 and 13 mu mag, respectively, in two of the best characterized non-oscillating Ap (noAp) stars. We announce 27 new rotational variables along with their rotation periods, and provide different rotation periods for seven other stars. Finally, we discuss how these results challenge state-of-the-art pulsation models for roAp stars.

  • 27.
    Das, Barnali
    et al.
    Tata Inst Fundamental Res, Natl Ctr Radio Astrophys, Pune Univ Campus, Pune 411007, Maharashtra, India..
    Chandra, Poonam
    Tata Inst Fundamental Res, Natl Ctr Radio Astrophys, Pune Univ Campus, Pune 411007, Maharashtra, India..
    Shultz, Matt E.
    Univ Delaware, Dept Phys & Astron, 217 Sharp Lab, Newark, DE 19716 USA..
    Wade, Gregg A.
    Royal Mil Coll Canada, Dept Phys & Space Sci, POB 17000, Kingston, ON K7K 7B4, Canada..
    Sikora, James
    Bishops Univ, Dept Phys & Astron, Sherbrooke, PQ J1M 1Z7, Canada..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Neiner, Coralie
    Univ Paris, Sorbonne Univ, CNRS, LESIA,Paris Observ,PSL Univ, 5 Pl Jules Janssen, F-92195 Meudon, France..
    Oksala, Mary E.
    Univ Paris, Sorbonne Univ, CNRS, LESIA,Paris Observ,PSL Univ, 5 Pl Jules Janssen, F-92195 Meudon, France.;Calif Lutheran Univ, Dept Phys, 60 W Olsen Rd, Thousand Oaks, CA 91360 USA..
    Alecian, Evelyne
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Discovery of Eight "Main-sequence Radio Pulse Emitters" Using the GMRT: Clues to the Onset of Coherent Radio Emission in Hot Magnetic Stars2022In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 925, no 2, article id 125Article in journal (Refereed)
    Abstract [en]

    Main-sequence radio pulse emitters (MRPs) are magnetic early-type stars from which periodic radio pulses, produced via electron cyclotron maser emission (ECME), are observed. Despite the fact that these stars can naturally offer suitable conditions for triggering ECME, only seven such stars have been reported so far within a span of more than two decades. In this paper, we report the discovery of eight more MRPs, thus more than doubling the sample size of such objects. These discoveries are the result of our sub-GHz observation program using the Giant Metrewave Radio Telescope over the years 2015-2021. Adding these stars to the previously known MRPs, we infer that at least 32% of the magnetic hot stars exhibit this phenomenon, thus suggesting that observation of ECME is not a rare phenomenon. The significantly larger sample of MRPs allows us for the first time to perform a statistical analysis comparing their physical properties. We present an empirical relation that can be used to predict whether a magnetic hot star is likely to produce ECME. Our preliminary analysis suggests that the physical parameters that play the primary role in the efficiency of the phenomenon are the maximum surface magnetic field strength and the surface temperature. In addition, we present strong evidence of the influence of the plasma density distribution on ECME pulse profiles. Results of this kind further motivate the search for MRPs, as a robust characterization of the relation between observed ECME properties and stellar physical parameters can only be achieved with a large sample.

  • 28.
    David-Uraz, A.
    et al.
    Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA.
    Neiner, C.
    Univ Paris Diderot, Sorbonne Univ, PSL Univ, LESIA,Observ Paris,CNRS,Sorbonne Paris Cite, 5 Pl Jules Janssen, F-92195 Meudon, France.
    Sikora, J.
    Queens Univ, Dept Phys Engn Phys & Astron, Kingston, ON K7L 3N6, Canada;Royal Mil Coll Canada, Dept Phys & Space Phys, POB 17000, Kingston, ON K7K 7B4, Canada.
    Bowman, D. M.
    Katholieke Univ Leuven, Inst Sterrenkunde, Celestijnenlaan 200D, B-3001 Leuven, Belgium.
    Petit, V.
    Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA.
    Chowdhury, S.
    Nicolaus Copernicus Astron Ctr, Bartycka 18, PL-00716 Warsaw, Poland.
    Handler, G.
    Nicolaus Copernicus Astron Ctr, Bartycka 18, PL-00716 Warsaw, Poland.
    Pergeorelis, M.
    Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA.
    Cantiello, M.
    Flatiron Inst, Ctr Computat Astrophys, 162 5th Ave, New York, NY 10010 USA;Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA.
    Cohen, D. H.
    Swarthmore Coll, Dept Phys & Astron, Swarthmore, PA 19081 USA.
    Erba, C.
    Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA.
    Keszthelyi, Z.
    Queens Univ, Dept Phys Engn Phys & Astron, Kingston, ON K7L 3N6, Canada;Royal Mil Coll Canada, Dept Phys & Space Phys, POB 17000, Kingston, ON K7K 7B4, Canada.
    Khalack, V.
    Univ Moncton, Dept Phys & Astron, Moncton, NB E1A 3E9, Canada.
    Kobzar, O.
    Univ Moncton, Dept Phys & Astron, Moncton, NB E1A 3E9, Canada.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Labadie-Bartz, J.
    Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Rua Matao 1226,Cidade Univ, BR-05508900 Sao Paulo, SP, Brazil.
    Lovekin, C. C.
    Mt Allison Univ, Dept Phys, Sackville, NB E4L 1E6, Canada.
    MacInnis, R.
    Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA.
    Owocki, S. P.
    Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA.
    Pablo, H.
    AAVSO Headquarters, 49 Bay State Rd, Cambridge, MA 02138 USA.
    Shultz, M. E.
    Univ Delaware, Dept Phys & Astron, Newark, DE 19716 USA.
    Ud-Doula, A.
    Penn State Scranton, 120 Ridge View Dr, Dunmore, PA 18512 USA.
    Wade, G. A.
    Royal Mil Coll Canada, Dept Phys & Space Phys, POB 17000, Kingston, ON K7K 7B4, Canada.
    Magnetic OB[A] Stars with TESS: probing their Evolutionary and Rotational properties (MOBSTER) - I. First-light observations of known magnetic B and A stars2019In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 487, no 1, p. 304-317Article in journal (Refereed)
    Abstract [en]

    In this paper we introduce the MOBSTER collaboration and lay out its scientific goals. We present first results based on the analysis of 19 previously known magnetic O, B, and A stars observed in 2-min cadence in sectors 1 and 2 of the Transiting Exoplanet Survey Satellite (TESS) mission. We derive precise rotational periods from the newly obtained light curves and compare them to previously published values. We also discuss the overall photometric phenomenology of the known magnetic massive and intermediate-mass stars and propose an observational strategy to augment this population by taking advantage of the high-quality observations produced by TESS.

  • 29.
    Dorn, R. J.
    et al.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Bristow, P.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Smoker, J. V.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Rodler, F.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Lavail, Alexis
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Accardo, M.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    van den Ancker, M.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Baade, D.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Baruffolo, A.
    INAF Osservatorio Astron Padova, Vicolo Osservatorio 5, I-35122 Padua, Italy..
    Courtney-Barrer, B.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Blanco, L.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Brucalassi, A.
    INAF Arcetri Osservatorio, Largo E Fermi 5, I-50125 Florence, Italy..
    Cumani, C.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Follert, R.
    Thuringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany..
    Haimerl, A.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Hatzes, A.
    Thuringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany..
    Haug, M.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Heiter, Ulrike
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Hinterschuster, R.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Hubin, N.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Ives, D. J.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Jung, Y.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Jones, M.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Kaeufl, H. -u.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Kirchbauer, J. -p.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Klein, B.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Korhonen, H. H.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Koehler, J.
    Thuringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany..
    Lizon, J-l.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Moins, C.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Molina-Conde, I.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Marquart, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Neeser, M.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Oliva, E.
    INAF Arcetri Osservatorio, Largo E Fermi 5, I-50125 Florence, Italy..
    Pallanca, L.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Pasquini, L.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Paufique, J.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Reiners, A.
    Univ Gottingen, Inst Astrophys, Friedrich Hund Pl 1, D-37077 Gottingen, Germany..
    Schneller, D.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Schmutzer, R.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Seemann, U.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Slumstrup, D.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Smette, A.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Stegmeier, J.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Stempels, Eric
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Tordo, S.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Valenti, E.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Valenzuela, J. J.
    European Southern Observ, Alonso Cordova 3107, Santiago, Vitacura, Chile..
    Vernet, J.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Vinther, J.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Munich, Germany..
    Wehrhahn, Ansgar
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    CRIRES+ on sky at the ESO Very Large Telescope: Observing the Universe at infrared wavelengths and high spectral resolution2023In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 671, article id A24Article in journal (Refereed)
    Abstract [en]

    The CRyogenic InfraRed Echelle Spectrograph (CRIRES) Upgrade project CRIRES+ extended the capabilities of CRIRES. It transformed this VLT instrument into a cross-dispersed spectrograph to increase the wavelength range that is covered simultaneously by up to a factor of ten. In addition, a new detector focal plane array of three Hawaii 2RG detectors with a 5.3 mu m cutoff wavelength replaced the existing detectors. Amongst many other improvements, a new spectropolarimetric unit was added and the calibration system has been enhanced. The instrument was installed at the VLT on Unit Telescope 3 at the beginning of 2020 and successfully commissioned and verified for science operations during 2021, partly remotely from Europe due to the COVID-19 pandemic. The instrument was subsequently offered to the community from October 2021 onwards. This article describes the performance and capabilities of the upgraded instrument and presents on sky results.

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  • 30. Drake, N.A.
    et al.
    Nesvacil, N.
    Hubrig, S.
    Kochukhov, Oleg
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Physics, Department of Astronomy and Space Physics. Department of Physics and Astronomy, Observational Astronomy.
    de la Reza, R.
    Polosukhina, N.
    Gonzales, J.F.
    Spectroscopic analysis of chemically peculiar stars: abundance determination of lithium and some rare earth elements2005In: IAUS 228, From Lithium to Uranium: Elemental Tracers of Early Cosmic Evolution, 2005, p. 89-Conference paper (Other scientific)
  • 31.
    Erba, C.
    et al.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Shultz, M. E.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Petit, V
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Fullerton, A. W.
    Space Telescope Sci Inst, Baltimore, MD 21218 USA..
    Henrichs, H. F.
    Univ Amsterdam, Anton Pannekoek Inst Astron, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Rivinius, T.
    European Org Astron Res Southern Hemisphere ESO, Casilla 19001, Santiago 19, Chile..
    Wade, G. A.
    Royal Mil Coll Canada, Dept Phys & Space Sci, Stn Forces, POB 17000, Kingston, ON K7K 0C6, Canada..
    Confirmation of ξ1 CMa’s ultra-slow rotation: magnetic polarity reversal and a dramatic change in magnetospheric UV emission lines2021In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 506, no 2, p. 2296-2308Article in journal (Refereed)
    Abstract [en]

    The magnetic beta Cep pulsator xi(1) CMa has the longest rotational period of any known magnetic B-type star. It is also the only magnetic B-type star with magnetospheric emission that is known to be modulated by both rotation and pulsation. We report here the first unambiguous detection of a negative longitudinal magnetic field in xi(1) CMa (< B-z > = -87 +/- 2 G in 2019 and < B-z > = -207 +/- 3 G in 2020), as well as the results of ongoing monitoring of the star's H alpha variability. We examine evidence for deviation from a purely dipolar topology. We also report a new HST UV spectrum of xi(1) CMa obtained near magnetic null that is consistent with an equatorial view of the magnetosphere, as evidenced by its similarity to the UV spectrum of beta Cep obtained near maximum emission. The new UV spectrum of xi(1) CMa provides additional evidence for the extremely long rotation period of this star via comparison to archival data.

  • 32.
    Farihi, J.
    et al.
    UCL, Dept Phys & Astron, London WC1E 6BT, England..
    Fossati, L.
    Austrian Acad Sci, Space Res Inst, A-8042 Graz, Austria..
    Wheatley, P. J.
    Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England..
    Metzger, B. D.
    Columbia Univ, Dept Phys, 538 W 120th St, New York, NY 10027 USA..
    Mauerhan, J.
    Univ Calif Berkeley, Dept Astron, 601 Campbell Hall, Berkeley, CA 94720 USA..
    Bachman, S.
    Indiana Univ Penn, Dept Phys, Indiana, PA 15705 USA.;Wesleyan Univ, Astron Dept, Middletown, CT 06459 USA.;Wesleyan Univ, Van Vleck Observ, Middletown, CT 06459 USA..
    Gänsicke, B. T.
    Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England..
    Redfield, S.
    Wesleyan Univ, Astron Dept, Middletown, CT 06459 USA.;Wesleyan Univ, Van Vleck Observ, Middletown, CT 06459 USA..
    Cauley, P. W.
    Wesleyan Univ, Astron Dept, Middletown, CT 06459 USA.;Wesleyan Univ, Van Vleck Observ, Middletown, CT 06459 USA..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Achilleos, N.
    UCL, Dept Phys & Astron, London WC1E 6BT, England..
    Stone, N.
    Columbia Univ, Dept Astron, New York, NY 10027 USA..
    Magnetism, X-rays and accretion rates in WD 1145+017 and other polluted white dwarf systems2018In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 474, no 1, p. 947-960Article in journal (Refereed)
    Abstract [en]

    This paper reports circular spectropolarimetry and X-ray observations of several polluted white dwarfs including WD 1145+017, with the aim to constrain the behaviour of disc material and instantaneous accretion rates in these evolved planetary systems. Two stars with previously observed Zeeman splitting, WD 0322-019 and WD 2105-820, are detected above 5 sigma and < B-z > > 1 kG, while WD 1145+017, WD 1929+011, and WD 2326+049 yield (null) detections below this minimum level of confidence. For these latter three stars, high-resolution spectra and atmospheric modelling are used to obtain limits on magnetic field strengths via the absence of Zeeman splitting, finding B-* < 20 kG based on data with resolving power R approximate to 40 000. An analytical framework is presented for bulk Earth composition material falling on to the magnetic polar regions of white dwarfs, where X-rays and cyclotron radiation may contribute to accretion luminosity. This analysis is applied to X-ray data for WD 1145+017, WD 1729+371, and WD 2326+049, and the upper bound count rates are modelled with spectra for a range of plasma kT = 1-10 keV in both the magnetic and non-magnetic accretion regimes. The results for all three stars are consistent with a typical dusty white dwarf in a steady state at 108-109 g s(-1). In particular, the non-magnetic limits for WD 1145+017 are found to be well below previous estimates of up to 10(12) g s(-1), and likely below 1010 g s(-1), thus suggesting the star-disc system may be average in its evolutionary state, and only special in viewing geometry.

  • 33. Folsom, C. P.
    et al.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Wade, G. A.
    Silvester, J.
    Bagnulo, S.
    Magnetic field, chemical composition and line profile variability of the peculiar eclipsing binary star AR Aur2010In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 407, no 4, p. 2383-2392Article in journal (Refereed)
    Abstract [en]

    AR Aur is the only eclipsing binary known to contain a HgMn star, making it an ideal case for a detailed study of the HgMn phenomenon. HgMn stars are a poorly understood class of chemically peculiar stars, which have traditionally been thought not to possess significant magnetic fields. However, the recent discovery of line profile variability in some HgMn stars, apparently attributable to surface abundance patches, has brought this belief into question. In this paper we investigate the chemical abundances, line profile variability, and magnetic field of the primary and secondary of the AR Aur system, using a series of high-resolution spectropolarimetric observations. We find the primary is indeed a HgMn star, and present the most precise abundances yet determined for this star. We find the secondary is a weak Am star, and is possibly still on the pre-main sequence. Line profile variability was observed in a range of lines in the primary, and is attributed to inhomogeneous surface distributions of some elements. No magnetic field was detected in any observation of either stars, with an upper limit on the longitudinal magnetic field in both stars of 100 G. Modelling of the phase-resolve longitudinal field measurements leads to a 3 Sigma upper limit on any dipole surface magnetic field of about 400 G.

  • 34. Folsom, C. P.
    et al.
    Likuski, K.
    Wade, G. A.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Alecian, E.
    Shulyak, D.
    Orbital parameters, chemical composition and magnetic field of the Ap binary HD 980882013In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 431, no 2, p. 1513-1527Article in journal (Refereed)
    Abstract [en]

    HD 98088 is a synchronized, double-lined spectroscopic binary system with a magnetic Ap primary component and an Am secondary component. We study this rare system using high-resolution Multi-Site Continuous Spectroscopy spectropolarimetric data, to gain insight into the effect of binarity on the origin of stellar magnetism and the formation of chemical peculiarities in A-type stars. Using a new collection of 29 high-resolution Stokes VQU spectra we re-derive the orbital and stellar physical parameters and conduct the first disentangling of spectroscopic observations of the system to conduct spectral analysis of the individual stellar components. From this analysis we determine the projected rotational velocities of the stars and conduct a detailed chemical abundance analysis of each component using both the SYNTH3 and ZEEMAN spectrum synthesis codes. The surface abundances of the primary component are typical of a cool Ap star, while those of the secondary component are typical of an Am star. We present the first magnetic analysis of both components using modern data. Using least-squares deconvolution, we extract the longitudinal magnetic field strength of the primary component, which is observed to vary between +1170 and -920 G with a period consistent with the orbital period. There is no field detected in the secondary component. The magnetic field in the primary is predominantly dipolar, with the positive pole oriented approximately towards the secondary.

  • 35. Fossati, L.
    et al.
    Ayres, T. R.
    Haswell, C. A.
    Bohlender, D.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Floeer, L.
    Absorbing gas around the WASP-12 planetary system2013In: ASTROPHYSICAL JOURNAL LETTERS, ISSN 2041-8205, Vol. 766, no 2, p. L20-Article in journal (Refereed)
    Abstract [en]

    Near-UV observations of the planet host star WASP-12 uncovered the apparent absence of the normally conspicuous core emission of the Mg II h and k resonance lines. This anomaly could be due either to (1) a lack of stellar activity, which would be unprecedented for a solar-like star of the imputed age of WASP-12 or (2) extrinsic absorption, from the intervening interstellar medium (ISM) or from material within the WASP-12 system itself, presumably ablated from the extreme hot Jupiter WASP-12 b. HIRES archival spectra of the Ca II H and K lines of WASP-12 show broad depressions in the line cores, deeper than those of other inactive and similarly distant stars and similar to WASP-12's Mg II h and k line profiles. We took high-resolution ESPaDOnS and FIES spectra of three early-type stars within 20' of WASP-12 and at similar distances, which show the ISM column is insufficient to produce the broad Ca II depression observed in WASP-12. The EBHIS H I column density map supports and strengthens this conclusion. Extrinsic absorption by material local to the WASP-12 system is therefore the most likely cause of the line core anomalies. Gas escaping from the heavily irradiated planet could form a stable and thick circumstellar disk/cloud. The anomalously low stellar activity index (logR'(HK)) of WASP-12 is evidently a direct consequence of the extra core absorption, so similar HK index deficiencies might signal the presence of translucent circumstellar gas around other stars hosting evaporating planets.

  • 36. Fossati, L.
    et al.
    Ayres, T. R.
    Haswell, C. A.
    Jenkins, J. S.
    Bisikalo, D.
    Bohlender, D.
    Floer, L.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Searching for a gas cloud surrounding the WASP-18 planetary system2014In: Astrophysics and Space Science, ISSN 0004-640X, E-ISSN 1572-946X, Vol. 354, no 1, p. 21-28Article in journal (Refereed)
    Abstract [en]

    Near-UV (NUV) Hubble Space Telescope (HST) observations of the extreme hot-Jupiter WASP-12b revealed the presence of diffuse exospheric gas extending beyond the planet's Roche lobe. Furthermore the NUV observations showed a complete lack of the normally bright core emission of the Mg ii h&k resonance lines, in agreement with the measured anomalously low stellar activity index (logR' (HK) ). Comparisons with other distant and inactive stars, and the analysis of radio and optical measurements of the intervening interstellar medium (ISM), led us to the conclusion that the system is surrounded by a circumstellar gas cloud, likely formed of material lost by the planet. Similar anomalous logR' (HK) index deficiencies might therefore signal the presence of translucent circumstellar gas around other stars hosting evaporating planets; we identified five such systems and WASP-18 is one of them. Both radio and optical observations of the region surrounding WASP-18 point towards a negligible ISM absorption along the WASP-18 line of sight. Excluding the unlikely possibility of an intrinsic anomalously low stellar activity, we conclude that the system is probably surrounded by a circumstellar gas cloud, presumably formed of material lost by the planet. Nevertheless only a far-UV spectrum of the star would provide a definite answer. Theoretical modelling suggests WASP-18b undergoes negligible mass loss, in contrast to the probable presence of a circumstellar gas cloud formed of material lost by the planet. The solution might be the presence either of an extra energy source driving mass loss (e.g., the reconnection of the stellar and planetary magnetic fields inside the planet atmosphere) or of an evaporating third body (e.g., moon).

  • 37. Fossati, L.
    et al.
    Bagnulo, S.
    Elmasli, A.
    Haswell, C. A.
    Holmes, S.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Shkolnik, E. L.
    Shulyak, D. V.
    Bohlender, D.
    Albayrak, B.
    Froning, C.
    Hebb, L.
    A detailed spectropolarimetric analysis of the planet-hosting star WASP-122010In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 720, no 1, p. 872-886Article in journal (Refereed)
    Abstract [en]

    The knowledge of accurate stellar parameters is paramount in several fields of stellar astrophysics, particularly in the study of extrasolar planets, where often the star is the only visible component and therefore used to infer the planet's fundamental parameters. Another important aspect of the analysis of planetary systems is the stellar activity and the possible star planet interaction. Here, we present a self-consistent abundance analysis of the planet-hosting star WASP-12 and a high-precision search for a structured stellar magnetic field on the basis of spectropolarimetric observations obtained with the ESPaDOnS spectropolarimeter. Our results show that the star does not have a structured magnetic field, and that the obtained fundamental parameters are in good agreement with what was previously published. In addition, we derive improved constraints on the stellar age (1.0-2.65 Gyr), mass (1.23-1.49 M/M-circle dot), and distance (295-465 pc). WASP-12 is an ideal object in which to look for pollution signatures in the stellar atmosphere. We analyze the WASP-12 abundances as a function of the condensation temperature and compare them with those published by several other authors on planet-hosting and non-planet-hosting stars. We find hints of atmospheric pollution in WASP-12's photosphere but are unable to reach firm conclusions with our present data. We conclude that a differential analysis based on WASP-12 twins will probably clarify whether an atmospheric pollution is present as well as the nature of this pollution and its implications in planet formation and evolution. We also attempt the direct detection of the circumstellar disk through infrared excess, but without success.

  • 38.
    Fossati, L.
    et al.
    Univ Bonn, Argelander Inst Astron, Bonn, Germany..
    Bagnulo, S.
    Armagh Observ, Armagh BT61 9DG, North Ireland..
    Landstreet, J. D.
    Univ Western Ontario, London, ON, Canada..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy. Uppsala Univ, Uppsala, Sweden..
    Comprehensive and Critical Reanalysis of FORS Spectropolarimetric Observations: the Case of HD922072015In: Physics and Evolution of Magnetic and Related Stars, 2015, Vol. 494, p. 63-75Conference paper (Refereed)
    Abstract [en]

    Stellar spectropolarimetry has become extremely popular during the past decade, and has led to major advances in our understanding of stellar magnetic fields and their impact on stellar structure and evolution. Many important discoveries have been made thanks to the observations performed with the FORS low-resolution spectropolarimeters of the ESO Very Large Telescope. We first review and summarize the major results of a homogeneous re-reduction and analysis of all single-slit FORS1 spectropolarimetric observations. This work revealed a non-negligible dependence of the results upon the adopted reduction and analysis procedure, as well as the presence of instabilities, revealing that photon noise is not the only source of uncertainty. As a consequence of our new analysis and assessment of uncertainties, we are not able to confirm a large number of magnetic field detections presented in the past for a variety of stars. We further summarize the results of FORS2 spectropolarimetric observations of the A0 supergiant HD92207, which allowed us to explore further the nature of the instabilities, roughly constraining their maximum impact on the derived Stokes profiles and magnetic field values. We finally present new results obtained with a further independent pipeline on the FORS2 data of HD92207, confirming our previous analysis, and discuss simple quality-check controls, which can be performed on the data in order to distinguish between the genuine and spurious signals. All together, our results reveal that the FORS spectropolarimeters are indeed reliable instruments when their capabilities are not pushed beyond the limits of the mounted Cassegrain low-resolution spectrograph.

  • 39. Fossati, L.
    et al.
    Bagnulo, S.
    Monier, R.
    Khan, S.A.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Astronomy and Space Physics, Observational Astronomy.
    Landstreet, J.
    Wade, G.
    Weiss, W.
    Late stages of the evolution of A-type stars on the main sequence: Comparison between observed chemical abundances and diffusion models for 8 Am stars of the Praesepe cluster2007In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 476, no 2, p. 911-925Article in journal (Refereed)
    Abstract [en]

    Aims. We aim to provide observational constraints on diffusion models that predict peculiar chemical abundances in the atmospheres of Am stars. We also intend to check if chemical peculiarities and slow rotation can be explained by the presence of a weak magnetic field. Methods. We have obtained high resolution, high signal-to-noise ratio spectra of eight previously-classified Am stars, two normal A-type stars and one Blue Straggler, considered to be members of the Praesepe cluster. For all of these stars we have determined fundamental parameters and photospheric abundances for a large number of chemical elements, with a higher precision than was ever obtained before for this cluster. For seven of these stars we also obtained spectra in circular polarization and applied the LSD technique to constrain the longitudinal magnetic field. Results. No magnetic field was detected in any of the analysed stars. HD 73666, a Blue Straggler previously considered as an Ap (Si) star, turns out to have the abundances of a normal A-type star. Am classification is not confirmed for HD 72942. For HD 73709 we have also calculated synthetic Aa photometry that is in good agreement with the observations. There is a generally good agreement between abundance predictions of diffusion models and values that we have obtained for the remaining Am stars. However, the observed Na and S abundances deviate from the predictions by 0.6 dex and ≥0.25 dex respectively. Li appears to be overabundant in three stars of our sample.

  • 40. Fossati, L.
    et al.
    Folsom, C. P.
    Bagnulo, S.
    Grunhut, J. H.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Landstreet, J. D.
    Paladini, C.
    Wade, G. A.
    A detailed spectroscopic analysis of the open cluster NGC 54602011In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 413, no 2, p. 1132-1144Article in journal (Refereed)
    Abstract [en]

    Within the context of a large project aimed at studying early F-, A- and late B-type stars, we present the abundance analysis of the photospheres of 21 members of the open cluster NGC 5460, an intermediate-age cluster (log t similar to 8.2) previously not studied with spectroscopy. Our study is based on medium- and high-resolution spectra obtained with the Fibre Large Array Multi Element Spectrograph (FLAMES) instrument of the European Southern Observatory/Very Large Telescope. We show that cluster members have a nearly solar metallicity and that there is evidence that the abundances of magnesium and iron are correlated with the effective temperature, exhibiting a maximum around T-eff = 10 500 K. No correlations are found between abundances and projected equatorial velocity, except for marginal evidence of barium being more abundant in slower than in faster rotating stars. We discovered two He-weak stars and a binary system where the hotter component is an HgMn star. We provide new estimates for the cluster distance (720 +/- 50 pc), age (log t = 8.2 +/- 0.1) and mean radial velocity (-17.9 +/- 5.2 km s-1).

  • 41. Fossati, L.
    et al.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Jenkins, J. S.
    Stancliffe, R. J.
    Haswell, C. A.
    Elmasli, A.
    Nickson, E.
    Detection of a magnetic field in three old and inactive solar-like planet-hosting stars2013In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 551, p. A85-Article in journal (Refereed)
    Abstract [en]

    Aims. Our understanding of magnetic fields in late-type stars is strongly driven by what we know of the solar magnetic field. For this reason, it is crucial to understand how typical the solar dynamo is. To do this we need to compare the solar magnetic field with that of other stars as similar to the Sun as possible, both in stellar parameters and age, hence activity. We present here the detection of a magnetic field in three planet-hosting solar-like stars having a mass, age, and activity level comparable to that of the Sun. Methods. We used the HARPSpol spectropolarimeter to obtain high-resolution high-quality circularly polarised spectra of HD 70642, HD 117207, and HD 154088, using the least-squares deconvolution technique to detect the magnetic field. From the Stokes I spectra, we calculated the log R'(HK) activity index for each star. We compared the position of the stars in the Hertzsprung-Russell diagram to evolutionary tracks, to estimate their mass and age. We used the lithium abundance, derived from the Stokes I spectra, to further constrain the ages. Results. We obtained a definite magnetic field detection for both HD 70642 and HD 154088, while for HD 117207 we obtained a marginal detection. Due to the lower signal-to-noise ratio of the observations, we were unable to detect the magnetic field in the second set of observations available for HD 117207 and HD 154088. On the basis of effective temperature, mass, age, and activity level the three stars can be considered solar analogs. Conclusions. HD 70642, HD 117207, and HD 154088 are ideal targets for a comparative study between the solar magnetic field and that of solar analogs.

  • 42. Fossati, L.
    et al.
    Kolenberg, K.
    Shulyak, D. V.
    Elmasli, A.
    Tsymbal, V.
    Barnes, T. G.
    Guggenberger, E.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    An in-depth spectroscopic analysis of RR Lyr Variations over the pulsation cycle2014In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 445, no 4, p. 4094-4104Article in journal (Refereed)
    Abstract [en]

    The stellar parameters of RR Lyrae stars vary considerably over a pulsation cycle, and their determination is crucial for stellar modelling. We present a detailed spectroscopic analysis of the pulsating star RR Lyr, the prototype of its class, over a complete pulsation cycle, based on high-resolution spectra collected at the 2.7-m telescope of McDonald Observatory. We used simultaneous photometry to determine the accurate pulsation phase of each spectrum and determined the effective temperature, the shape of the depth-dependent microturbulent velocity, and the abundance of several elements, for each phase. The surface gravity was fixed to 2.4. Element abundances resulting from our analysis are stable over the pulsation cycle. However, a variation in ionization equilibrium is observed around minimum radius. We attribute this mostly to a dynamical acceleration contributing to the surface gravity. Variable turbulent convection on time-scales longer than the pulsation cycle has been proposed as a cause for the Blazhko effect. We test this hypothesis to some extent by using the derived variable depth-dependent microturbulent velocity profiles to estimate their effect on the stellar magnitude. These effects turn out to be wavelength dependent and much smaller than the observed light variations over the Blazhko cycle: if variations in the turbulent motions are entirely responsible for the Blazhko effect, they must surpass the scales covered by the microturbulent velocity. This work demonstrates the possibility of a self-consistent spectroscopic analysis over an entire pulsation cycle using static atmosphere models, provided one takes into account certain features of a rapidly pulsating atmosphere.

  • 43.
    Goffo, Elisa
    et al.
    Univ Torino, Dipartimento Fis, Via Pietro Giuria 1, I-10125 Turin, Italy.;Thuringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany..
    Gandolfi, Davide
    Univ Torino, Dipartimento Fis, Via Pietro Giuria 1, I-10125 Turin, Italy..
    Egger, Jo Ann
    Univ Bern, Phys Inst, Gesell Str 6, CH-3012 Bern, Switzerland..
    Mustill, Alexander J.
    Lund Univ, Dept Phys, Div Astrophys, Lund Observ, POB 43, SE-22100 Lund, Sweden.;Lund Univ, Dept Astron & Theoret Phys, Lund Observ, POB 43, SE-22100 Lund, Sweden..
    Albrecht, Simon H.
    Aarhus Univ, Stellar Astrophys Ctr, Dept Phys & Astron, Ny Munkegade 120, DK-8000 Aarhus C, Denmark..
    Hirano, Teruyuki
    Astrobiol Ctr, 2-21-1 Osawa, Mitaka, Tokyo 1818588, Japan.;Natl Astron Observ Japan, 2-21-1 Osawa, Mitaka, Tokyo 1818588, Japan..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Astudillo-Defru, Nicola
    Univ Catolica Santisima Concepcion, Dept Matemat & Fis Aplicadas, Alonso de Rivera 2850, Concepcion, Chile..
    Barragan, Oscar
    Univ Oxford, Subdept Astrophys, Dept Phys, Oxford OX1 3RH, England..
    Serrano, Luisa M.
    Univ Torino, Dipartimento Fis, Via Pietro Giuria 1, I-10125 Turin, Italy..
    Hatzes, Artie P.
    Thuringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany..
    Alibert, Yann
    Univ Bern, Phys Inst, Gesell Str 6, CH-3012 Bern, Switzerland.;Univ Bern, Ctr Space & Habitabil, Gesell Str 6, CH-3012 Bern, Switzerland..
    Guenther, Eike
    Thuringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany..
    Dai, Fei
    Div Geol & Planetary Sci, 1200 Calif Blvd, Pasadena, CA 91125 USA.;CALTECH, Dept Astron, Pasadena, CA 91125 USA..
    Lam, Kristine W. F.
    German Aerosp Ctr DLR, Inst Planetary Res, Rutherfordstr 2, D-12489 Berlin, Germany..
    Csizmadia, Szilard
    German Aerosp Ctr DLR, Inst Planetary Res, Rutherfordstr 2, D-12489 Berlin, Germany..
    Smith, Alexis M. S.
    German Aerosp Ctr DLR, Inst Planetary Res, Rutherfordstr 2, D-12489 Berlin, Germany..
    Fossati, Luca
    Austrian Acad Sci, Space Res Inst, Schmiedlstr 6, A-8042 Graz, Austria..
    Luque, Rafael
    Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA..
    Rodler, Florian
    European Southern Observ, Alonso de Cordova 3107, Santiago Se Chile, Chile..
    Winther, Mark L.
    Aarhus Univ, Stellar Astrophys Ctr, Dept Phys & Astron, Ny Munkegade 120, DK-8000 Aarhus C, Denmark..
    Rørsted, Jakob L.
    Aarhus Univ, Stellar Astrophys Ctr, Dept Phys & Astron, Ny Munkegade 120, DK-8000 Aarhus C, Denmark..
    Alarcon, Javier
    European Southern Observ, Alonso de Cordova 3107, Santiago Se Chile, Chile..
    Bonfils, Xavier
    Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France..
    Cochran, William D.
    Univ Texas Austin, McDonald Observ, Austin, TX USA.;Univ Texas Austin, Ctr Planetary Syst Habitabil, Austin, TX USA..
    Deeg, Hans J.
    Inst Astrofis Canarias IAC, E-38205 San Cristobal la Laguna, Tenerife, Spain.;Univ La Laguna ULL, Dept Astrofis, E-38206 San Cristobal la Laguna, Tenerife, Spain..
    Jenkins, Jon M.
    NASA Ames Res Ctr, Moffett Field, CA 94035 USA..
    Korth, Judith
    Lund Univ, Dept Phys, Div Astrophys, Lund Observ, POB 43, SE-22100 Lund, Sweden..
    Livingston, John H.
    Astrobiol Ctr, 2-21-1 Osawa, Mitaka, Tokyo 1818588, Japan.;Natl Astron Observ Japan, 2-21-1 Osawa, Mitaka, Tokyo 1818588, Japan.;Grad Univ Adv Studies SOKENDAI, Sch Phys Sci, Dept Astron Sci, 2-21-1 Osawa, Mitaka, Tokyo 1818588, Japan..
    Meech, Annabella
    Univ Oxford, Dept Phys, Keble Rd, Oxford OX1 3RH, England..
    Murgas, Felipe
    Inst Astrofis Canarias IAC, E-38205 San Cristobal la Laguna, Tenerife, Spain.;Univ La Laguna ULL, Dept Astrofis, E-38206 San Cristobal la Laguna, Tenerife, Spain..
    Orell-Miquel, Jaume
    Inst Astrofis Canarias IAC, E-38205 San Cristobal la Laguna, Tenerife, Spain.;Univ La Laguna ULL, Dept Astrofis, E-38206 San Cristobal la Laguna, Tenerife, Spain..
    Osborne, Hannah L. M.
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Palle, Enric
    Inst Astrofis Canarias IAC, E-38205 San Cristobal la Laguna, Tenerife, Spain.;Univ La Laguna ULL, Dept Astrofis, E-38206 San Cristobal la Laguna, Tenerife, Spain..
    Persson, Carina M.
    Chalmers Univ Technol, Dept Space Earth & Environm, Onsala Space Observ, SE-43992 Onsala, Sweden..
    Redfield, Seth
    Wesleyan Univ, Astron Dept, Middletown, CT 06459 USA.;Wesleyan Univ, Van Vleck Observ, Middletown, CT 06459 USA..
    Ricker, George R.
    MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA.;MIT, Phys Dept, Cambridge, MA USA..
    Seager, Sara
    MIT, Dept Earth Atmospher & Planetary Sci, Cambridge, MA 02139 USA.;MIT, Dept Phys, Cambridge, MA 02139 USA.;MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA.;MIT, Dept Aeronaut & Astronaut, Cambridge, MA 02139 USA..
    Vanderspek, Roland
    MIT, Dept Phys, Cambridge, MA 02139 USA.;MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA..
    Van Eylen, Vincent
    Univ Coll London, Mullard Space Sci Lab, Dorking RH5 6NT, Surrey, England..
    Winn, Joshua N.
    Princeton Univ, Dept Astrophys Sci, Princeton, NJ 08544 USA..
    Company for the Ultra-high Density, Ultra-short Period Sub-Earth GJ 367 b: Discovery of Two Additional Low-mass Planets at 11.5 and 34 Days2023In: Astrophysical Journal Letters, ISSN 2041-8205, E-ISSN 2041-8213, Vol. 955, no 1, article id L3Article in journal (Refereed)
    Abstract [en]

    GJ 367 is a bright (V approximate to 10.2) M1 V star that has been recently found to host a transiting ultra-short period subEarth on a 7.7 hr orbit. With the aim of improving the planetary mass and radius and unveiling the inner architecture of the system, we performed an intensive radial velocity follow-up campaign with the HARPS spectrograph-collecting 371 high-precision measurements over a baseline of nearly 3 yr-and combined our Doppler measurements with new TESS observations from sectors 35 and 36. We found that GJ 367 b has a mass of M-b = 0.633 +/- 0.050M. and a radius of R-b = 0.699 +/- 0.024 R-circle plus, corresponding to precisions of 8% and 3.4%, respectively. This implies a planetary bulk density of rho(b) = 10.2 +/- 1.3 g cm(-3), i.e., 85% higher than Earth's density. We revealed the presence of two additional non-transiting low-mass companions with orbital periods of similar to 11.5 and 34 days and minimum masses of M-c sin i(c) = 4.13 +/- 0.36 M-circle plus and M-d sin i(d) = 6.03 +/- 0.49M(circle plus), respectively, which lie close to the 3:1 mean motion commensurability. GJ 367 b joins the small class of highdensity planets, namely the class of super-Mercuries, being the densest ultra-short period small planet known to date. Thanks to our precise mass and radius estimates, we explored the potential internal composition and structure of GJ 367 b, and found that it is expected to have an iron core with a mass fraction of 0.91(-0.23)(+0.07). How this iron core is formed and how such a high density is reached is still not clear, and we discuss the possible pathways of formation of such a small ultra-dense planet.

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  • 44.
    Grunhut, J. H.
    et al.
    Telus Digital, 25 York St, Toronto, ON M5J 2V5, Canada..
    Wade, G. A.
    Royal Mil Coll Canada, Dept Phys & Space Sci, Stn Forces, POB 17000, Kingston, ON K7K7B4, Canada..
    Folsom, C. P.
    Royal Mil Coll Canada, Dept Phys & Space Sci, Stn Forces, POB 17000, Kingston, ON K7K7B4, Canada.;Univ Tartu, Tartu Observ, Observatooriumi 1, EE-61602 Toravere, Estonia..
    Neiner, C.
    Sorbonne Univ, PSL Univ, Univ Paris, Paris Observ,CNRS,LESIA, 5 Pl Jules Janssen, F-92195 Meudon, France..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Alecian, E.
    Univ Grenoble Alpes, IPAG, CNRS, F-38000 Grenoble, France..
    Shultz, M.
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    Petit, V
    Univ Delaware, Bartol Res Inst, Dept Phys & Astron, Newark, DE 19716 USA..
    The magnetic field and magnetosphere of Plaskett's star: a fundamental shift in our understanding of the system2022In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 512, no 2, p. 1944-1966Article in journal (Refereed)
    Abstract [en]

    Plaskett's 'star' appears to be one of a small number of short-period binary systems known to contain a hot, massive, magnetic star. We combine an extensive spectropolarimetric (Stokes V) data set with archival photometry and spectropolarimetry to establish the essential characteristics of the magnetic field and magnetosphere of the rapidly rotating, broad-line component of the system. We apply least-squares deconvolution (LSD) to infer the longitudinal magnetic field from each Stokes V spectrum. Using the time series of longitudinal field measurements, in combination with CoRoT photometry and equivalent width measurements of magnetospheric spectral lines, we infer the rotation period of the magnetic star to be equal to 1.21551(-0.00034)(+0.00028) d. Modelling the Stokes V LSD profiles with Zeeman-Doppler Imaging, we produce the first reliable magnetic map of an O-type star. We find a magnetic field that is predominantly dipolar, with an obliquity near 90 degrees and a polar strength of about 850 G. We update the calculations of the theoretical magnetospheric parameters, and in agreement with their predictions we identify clear variability signatures of the H alpha, H beta, and He II lambda 4686 lines confirming the presence of a dense centrifugal magnetosphere surrounding the star. Finally, we report a lack of detection of radial velocity (RV) variations of the observed Stokes V profiles, suggesting that historical reports of the large RV variations of the broad-line star's spectral lines may be spurious. This discovery may motivate a fundamental revision of the historical model of the Plaskett's star as a near-equal mass O + O binary system.

  • 45.
    Grunhut, J. H.
    et al.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany.;Univ Toronto, Dunlap Inst Astron & Astrophys, 50 St George St, Toronto, ON M5S 3H4, Canada..
    Wade, G. A.
    Royal Mil Coll Canada, Dept Phys, POB 17000, Kingston, ON K7K 7B4, Canada..
    Neiner, C.
    Univ Paris Diderot, UPMC Univ Paris 06, Sorbonne Univ,Sorbonne Paris Cite, LESIA,Observ Paris,PSL Res Univ,CNRS, 5 Pl Jules Janssen, F-92195 Meudon, France..
    Oksala, M. E.
    Univ Paris Diderot, UPMC Univ Paris 06, Sorbonne Univ,Sorbonne Paris Cite, LESIA,Observ Paris,PSL Res Univ,CNRS, 5 Pl Jules Janssen, F-92195 Meudon, France.;Calif Lutheran Univ, Dept Phys, 60 West Olsen Rd 3700, Thousand Oaks, CA 91360 USA..
    Petit, V.
    Florida Inst Technol, Dept Phys & Space Sci, Melbourne, FL 32901 USA..
    Alecian, E.
    Univ Paris Diderot, UPMC Univ Paris 06, Sorbonne Univ,Sorbonne Paris Cite, LESIA,Observ Paris,PSL Res Univ,CNRS, 5 Pl Jules Janssen, F-92195 Meudon, France.;CNRS, INSU, UJF Grenoble 1, Inst Planetol & Astrophys Grenoble,UMR 5274, F-38041 Grenoble, France..
    Bohlender, D. A.
    Natl Res Council Canada, Herzberg Astron & Astrophys Program, Domin Astrophys Observ, 5071 West Saanich Rd, Victoria, BC V9E 2E7, Canada..
    Bouret, J. -C
    Henrichs, H. F.
    Univ Amsterdam, Anton Pannekoek Inst Astron, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands..
    Hussain, G. A. J.
    European Southern Observ, Karl Schwarzschild Str 2, D-85748 Garching, Germany..
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    The MiMeS survey of Magnetism in Massive Stars: magnetic analysis of the O-type stars2017In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 465, no 2, p. 2432-2470Article in journal (Refereed)
    Abstract [en]

    We present the analysis performed on spectropolarimetric data of 97 O-type targets included in the framework of the Magnetism in Massive Stars (MiMeS) Survey. Mean least-squares deconvolved Stokes I and V line profiles were extracted for each observation, from which we measured the radial velocity, rotational and non-rotational broadening velocities, and longitudinal magnetic field B-l. The investigation of the Stokes I profiles led to the discovery of two new multiline spectroscopic systems (HD 46106, HD 204827) and confirmed the presence of a suspected companion in HD 37041. We present a modified strategy of the leastsquares deconvolution technique aimed at optimizing the detection of magnetic signatures while minimizing the detection of spurious signatures in Stokes V. Using this analysis, we confirm the detection of a magnetic field in six targets previously reported as magnetic by the MiMeS collaboration (HD 108, HD 47129A2, HD 57682, HD 148937, CPD-28 2561, and NGC 1624-2), as well as report the presence of signal in Stokes V in three new magnetic candidates (HD 36486, HD 162978, and HD 199579). Overall, we find a magnetic incidence rate of 7 +/- 3 per cent, for 108 individual O stars (including all O-type components part of multiline systems), with a median uncertainty of the B-l measurements of about 50 G. An inspection of the data reveals no obvious biases affecting the incidence rate or the preference for detecting magnetic signatures in the magnetic stars. Similar to A- and B-type stars, we find no link between the stars' physical properties (e.g. T-eff, mass, and age) and the presence of a magnetic field. However, the Of?p stars represent a distinct class of magnetic O-type stars.

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  • 46.
    Hackman, T.
    et al.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland.
    Ilyin, I.
    Leibniz Inst Astrophys Potsdam AIP, Sternwarte 16, D-14482 Potsdam, Germany.
    Lehtinen, J. J.
    Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, D-37077 Gottingen, Germany;Aalto Univ, ReSoLVE Ctr Excellence, Dept Comp Sci, POB 15400, Aalto 00076, Finland.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Kaepylae, M. J.
    Max Planck Inst Solar Syst Res, Justus von Liebig Weg 3, D-37077 Gottingen, Germany;Aalto Univ, ReSoLVE Ctr Excellence, Dept Comp Sci, POB 15400, Aalto 00076, Finland.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Willamo, T.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00014, Finland.
    Starspot activity of HD199178 Doppler images from 1994-20172019In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 625, article id A79Article in journal (Refereed)
    Abstract [en]

    Context

    Studying the spots of late-type stars is crucial for distinguishing between the various proposed dynamo mechanisms believed to be the main cause of starspot activity. For this research it is important to collect observation time series that are long enough to unravel both long- and short-term spot evolution. Doppler imaging is a very efficient method for studying spots of stars that cannot be angularly resolved. Aims. High-resolution spectral observations during 1994-2017 are analysed in order to reveal long- and short-term changes in the spot activity of the FK Comae-type subgiant HD199178.

    Methods

    Most of the observations were collected with the Nordic Optical Telescope. The Doppler imaging temperature maps were calculated using an inversion technique based on Tikhonov regularisation and utilising multiple spectral lines.

    Results

    We present a unique series of 41 temperature maps spanning more than 23 years. All reliable images show a large cool spot region centred near the visible rotation pole. Some lower latitude cool features are also recovered, although the reliability of these is questionable. There is an expected anti-correlation between the mean surface temperature and the spot coverage. Using the Doppler images, we construct the equivalent of a solar butterfly diagram for HD199178.

    Conclusions

    HD199178 clearly has a long-term large and cool spot structure at the rotational pole. This spot structure dominated the spot activity during the years 1994-2017. The size and position of the structure has evolved with time, with a gradual increase during the last years. The lack of lower latitude features prevents the determination of a possible differential rotation.

  • 47.
    Hackman, T.
    et al.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00084, Finland..
    Lehtinen, J.
    Univ Helsinki, Dept Phys, POB 64, Helsinki 00084, Finland..
    Rosén, Lisa
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Kapyla, M. J.
    Aalto Univ, Dept Comp Sci, ReSoLVE Ctr Excellence, POB 15400, Aalto 00076, Finland..
    Zeeman-Doppler imaging of active young solar-type stars2016In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 587, article id A28Article in journal (Refereed)
    Abstract [en]

    Context: By studying young magnetically active late-type stars, i.e. analogues to the young Sun, we can draw conclusions on the evolution of the solar dynamo.

    Aims: We determine the topology of the surface magnetic field and study the relation between the magnetic field and cool photospheric spots in three young late-type stars.

    Methods: High-resolution spectropolarimetry of the targets was obtained with the HARPSpol instrument mounted at the ESO 3.6 m telescope. The signal-to-noise ratios of the Stokes IV measurements were boosted by combining the signal from a large number of spectroscopic absorption lines through the least squares deconvolution technique. Surface brightness and magnetic field maps were calculated using the Zeeman-Doppler imaging technique.

    Results: All three targets show clear signs of magnetic fields and cool spots. Only one of the targets, V1358 Ori, shows evidence of the dominance of non-axisymmetric modes. In two of the targets, the poloidal field is significantly stronger than the toroidal one, indicative of an alpha(2)-type dynamo, in which convective turbulence effects dominate over the weak differential rotation. In two of the cases there is a slight anti-correlation between the cool spots and the strength of the radial magnetic field. However, even in these cases the correlation is much weaker than in the case of sunspots.

    Conclusions: The weak correlation between the measured radial magnetic field and cool spots may indicate a more complex magnetic field structure in the spots or spot groups involving mixed magnetic polarities. Comparison with a previously published magnetic field map shows that on one of the stars, HD 29615, the underlying magnetic field changed its polarity between 2009 and 2013.

  • 48. Hackman, T.
    et al.
    Mantere, M. J.
    Jetsu, L.
    Ilyin, I.
    Kajatkari, P.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Lehtinen, J.
    Lindborg, M.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Tuominen, I.
    Spot activity of II Peg2011In: Astronomical Notes - Astronomische Nachrichten, ISSN 0004-6337, E-ISSN 1521-3994, Vol. 332, no 9-10, p. 859-865Article in journal (Refereed)
    Abstract [en]

    We have studied the long-term spot activity of the RS CVn star II Peg by means of Doppler imaging based on spectroscopy and time series analysis of photometry. We present 28 Doppler imaging temperature maps spanning the years 1994-2010, of which 14 were calculated for the present study. The longitudinal spot distribution, derived from the surface temperature maps, is compared with epochs of the light curve minima, derived from photometric observations. We detect a longitudinal drift in the major spot structure during 1995-2003. After this there is a clear decrease in the activity level and no clear drift can be seen. We conclude that the variations could be caused by a cyclic behaviour of the underlying magnetic dynamo.

  • 49. Hackman, T.
    et al.
    Mantere, M. J.
    Lindborg, M.
    Ilyin, I.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Tuominen, I.
    Doppler images of II Pegasi for 2004-20102012In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 538, p. A126-Article in journal (Refereed)
    Abstract [en]

    Aims. We study the spot activity of II Peg during the years 2004-2010 to determine long- and short-term changes in the magnetic activity. In a previous study, we detected a persistent active longitude, as well as major changes in the spot configuration occurring on a timescale of shorter than a year. The main objective of this study is to determine whether the same phenomena persist in the star during these six years of spectroscopic monitoring. Methods. The observations were collected with the high-resolution SOFIN spectrograph at the Nordic Optical Telescope. The temperature maps were calculated using a Doppler imaging code based on Tikhonov regularization. Results. We present 12 new temperature maps that show spots distributed mainly over high and intermediate latitudes. In each image, 1-3 main active regions can be identified. The activity level of the star is clearly lower than during our previous study for the years 1994-2002. In contrast to the previous observations, we detect no clear drift of the active regions with respect to the rotation of the star. Conclusions. Having shown a systematic longitudinal drift of the spot-generating mechanism during 1994-2002, the star has clearly switched to a low-activity state for 2004-2010, during which the spot locations appear more random over phase space. It could be that the star is near to a minimum of its activity cycle.

  • 50.
    Hahlin, Axel
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Kochukhov, Oleg
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Small-scale magnetic fields of the spectroscopic binary T Tauri stars V1878 Ori and V4046 Sgr2022In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 659, article id A151Article in journal (Refereed)
    Abstract [en]

    Y Aims. The goal of this study is to investigate the small-scale magnetic fields of the two spectroscopic binary T Tauri stars V1878 Ori and V4046 Sgr. This is done to complete the observational characterisation of the surface magnetic fields of these stars because only their large-scale magnetic fields have been studied with Zeeman Doppler imaging (ZDI) so far. Methods. To investigate the small-scale magnetic fields, the differential Zeeman intensification of near-infrared Ti I lines was investigated using high-resolution archival spectra obtained with the ESPaDOnS spectrograph at the CFHT. In order to study the binary components separately, the spectra were disentangled by considering observations taken at different orbital phases. The Zeeman-intensification analysis was performed based on detailed polarised radiative transfer calculations aided by the Markov chain Monte Carlo inference, treating magnetic field filling factors and other stellar parameters that could affect the spectra as free parameters. Results. The obtained average magnetic field strengths of the components of V1878 Ori are 1.33 +/- 0.08 and 1.57 +/- 0.09 kG, respectively. Previous ZDI studies of V1878 Ori recovered about 14 and 20% of this total magnetic field strength. For V4046 Sgr, the magnetic field strengths are 1.96 +/- 0.18 and 1.83 +/- 0.18 kG, respectively. In this case, about 12 and 9% of the total magnetic field strength was detected by ZDI. Conclusions. The small-scale magnetic field strengths obtained from Zeeman intensification are similar for the two components of each binary. This is in contrast to the large-scale magnetic fields obtained from ZDI investigations, performed using the same observations, which found that magnetic field strengths and topologies vary significantly in the components of the two binaries. While the large-scale field might look significantly different, the overall magnetic energy, primarily carried by the small-scale magnetic fields, appears to be quite similar. This indicates that the efficiency of the magnetic dynamo is comparable for the components of the two binaries.

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