Title of article :
Short-term variations in Be stars observed by the CoRoT and Kepler space missions
Author/Authors :
Juan Gutierrez-Soto، نويسنده , , Coralie Neiner، نويسنده , , Juan Fabregat، نويسنده , , Antonino Francesco Lanza، نويسنده , , Thierry Semaan، نويسنده , , Monica Rainer، نويسنده , , Ennio Poretti، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2010
Abstract :
The corot and kepler space missions are collecting very high-precision longduration photometric data of many Be stars, allowing us to better understand the origin of their short-term variability and the link between these variations and the Be phenomenon. In this paper, we present a brief summary of the results obtained in the analysis of several Be stars observed with corot in terms of pulsations. In addition, we show that variations of the Be star HD175869 can be explained as two active regions separated by 150 degrees or as unstable pulsating modes in a star with an extensive mixing in radiative layers corresponding to a core overshooting of 0.35Hp. A preliminary study of the photometric and spectroscopic variability seen in the B1.5IVe star HD51193 is performed. Currently the kepler satellite is observing the only confirmed Be star in its field of view, namely KIC 6954726. From low-resolution spectra we derived a spectral type of B2.5Ve for this star and we studied the long-term variation of the emission in the Hα line. The 3.5-year kepler light curve will allow us to detect even more close frequencies than with corot and to perform a detailed analysis of the amplitude variations in a Be star.
Keywords :
stars: emission-line , Be , stars: oscillations
Journal title :
Proceedings of the International Astronomical Union
Journal title :
Proceedings of the International Astronomical Union