New H-Band Stellar Spectral Libraries for the SdSS-III/Apogee Survey
2015 (English)In: Astronomical Journal, ISSN 0004-6256, E-ISSN 1538-3881, Vol. 149, no 6, 181Article in journal (Refereed) Published
The Sloan Digital Sky Survey-III (SDSS-III) Apache Point Observatory Galactic Evolution Experiment (APOGEE) has obtained high-resolution (R similar to 22,500), high signal-to-noise ratio (>100) spectra in the H-band (similar to 1.5-1.7 mu m) for about 146,000 stars in the Milky Way galaxy. We have computed spectral libraries with effective temperature (T-eff) ranging from 3500 to 8000 K for the automated chemical analysis of the survey data. The libraries, used to derive stellar parameters and abundances from the APOGEE spectra in the SDSS-III data release 12 (DR12), are based on ATLAS9 model atmospheres and the ASS epsilon T spectral synthesis code. We present a second set of libraries based on MARCS model atmospheres and the spectral synthesis code Turbospectrum. The ATLAS9/ASS epsilon T (T-eff = 3500-8000 K) and MARCS/Turbospectrum (T-eff = 3500-5500 K) grids cover a wide range of metallicity (-2.5 <= [M/H] <= + 0.5 dex), surface gravity (0 <= log g <= 5 dex), microturbulence (0.5 <= xi <= 8 km s(-1)), carbon (-1 <= [C/M] <= + 1 dex), nitrogen (-1 <= [N/M] <= + 1 dex), and alpha-element (-1 <= [alpha/M] <= + 1 dex) variations, having thus seven dimensions. We compare the ATLAS9/ASS.T and MARCS/Turbospectrum libraries and apply both of them to the analysis of the observed H-band spectra of the Sun and the K2 giant Arcturus, as well as to a selected sample of well-known giant stars observed at very high resolution. The new APOGEE libraries are publicly available and can be employed for chemical studies in the H-band using other high-resolution spectrographs.
Place, publisher, year, edition, pages
2015. Vol. 149, no 6, 181
astrochemistry, radiative transfer, stars: atmospheres
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:uu:diva-256810DOI: 10.1088/0004-6256/149/6/181ISI: 000355250400004OAI: oai:DiVA.org:uu-256810DiVA: diva2:827764