Spectroscopic study of pulsations in the atmosphere of roAp star 10 Aql
2008 (English)In: Contributions of the Astronomical Observatory Skalnate Pleso, ISSN 1335-1842, Vol. 38, no 2, 323-328 p.Article in journal (Refereed) Published
We present the analysis of spectroscopic time-series observations of the roAp star 10 Aql. Observations were carried out in July 2006 with the UVES and SARG spectrographs and simultaneously with the MOST mini-satellite photometry. All these data were analysed for radial velocity (RV) variations. About 150 lines out of the 1000 measured reveal a clear pulsation signal. Frequency analysis of the spectroscopic data gives three frequencies that coincide with the photometric ones. Phase-amplitude diagrams created for the lines of different elements/ions show that atmospheric pulsations may be represented by a superposition of standing and running wave components, similar to other roAp stars. The highest RV amplitudes, 300-400 ms(-1), were measured for Ce II, Dy III, Tb III, and two unidentified lines at lambda 5471, 5556 angstrom. We discovered a approximate to 0.4 period phase jump in the RV measurements across the Nd III line profiles, indicating the presence of the pulsation node in stellar atmospheres. The phase jump occurs at nearly the same atmospheric layer for the two main frequencies. There is no rotational modulation in the average spectra for the 6 different nights we analysed.
Place, publisher, year, edition, pages
2008. Vol. 38, no 2, 323-328 p.
stars : atmospheres, stars : chemically peculiar, stars : magnetic fields, stars : oscillations, stars : individual : 10 Aql (HD 176232)
IdentifiersURN: urn:nbn:se:uu:diva-149674ISI: 000256514000034OAI: oai:DiVA.org:uu-149674DiVA: diva2:405824
Conference Information: CP/AP Workshop 2007
Vienna, AUSTRIA, SEP 10-14, 20072011-03-232011-03-222011-03-23Bibliographically approved