Asteroseismology; red giants; solar-like oscillations
Abstract :
[en] Corot and Kepler observations of red giants reveal rich spectra of non-radial solar-like oscillations allowing to probe their internal structure. We compare the theoretical spectrum (amplitudes and life- times) of two red giants in the same region of the HR diagram but in different evolutionary phases. The lifetimes are obtained by computing theoretical non-adiabatic non-radial solar-like oscillations for mixed modes in the two models. Thanks to this, we have been able to compute the oscillation amplitudes through a stochastic excitation model. We present here our first results on the inertia, damping rates and amplitudes of the oscillations in the two stars and discuss the trapping, the visibilities and the am- plitudes of the different modes. The differences in the spectra of the two stars are also investigated. As already known, the period spacings in the two models are very different. Moreover, we find significant differences in amplitudes and lifetimes between the two models.
Research Center/Unit :
Groupe d'Astrophysique Stellaire Théorique et Astérosismologie
Dupret, Marc-Antoine ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie
Belkacem, Kevin
Montalban Iglesias, Josefa ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie
Noels-Grötsch, Arlette ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Département d'astrophys., géophysique et océanographie (AGO)
Samadi, Réza
Language :
English
Title :
Non-radial, non-adiabatic solar-like oscillations in RGB and HB stars
Alternative titles :
[fr] Oscillations non-radiales de type solaire, dans les étoiles de la RGB et de la branche horizontale : Calculs non-adiabatiques.
Publication date :
July 2012
Number of pages :
A0
Event name :
40th Liège International Astrophysical Colloquium
Event place :
Liège, Belgium
Event date :
du 9 au 13 juillet 2012
Audience :
International
Name of the research project :
Energetic study of solar-like oscillations in red-giants
Funders :
FRIA - Fonds pour la Formation à la Recherche dans l'Industrie et dans l'Agriculture [BE]