[en] We apply here the Time Dependent Convection (TDC) treatment presented in our earlier paper in this series to the study of delta Sct and gamma Dor pulsating stars. Stabilization of the delta Sct p-modes at the red edge of the Instability Strip (IS) and the driving of the gamma Dor g-modes are explained by our models. Theoretical IS obtained with different values of the Mixing Length (ML) parameter alpha are compared to observations and a good agreement is obtained for alpha between 1.8 and 2. The influence of each term of our TDC treatment (perturbation of convective flux, turbulent pressure, and turbulent kinetic energy dissipation) on the eigenfrequencies and on the driving and damping mechanisms is investigated. Finally, we show that our TDC models predict the likely existence of hybrid stars with both delta Sct p-modes and gamma Dor g-modes oscillations.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Dupret, Marc-Antoine ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique
Grigahcène, A.; Instituto de Astrofísica de Andalucía-CSIC, Apartado 3004, 18080 Granada, Spain
Garrido, R.; Instituto de Astrofísica de Andalucía-CSIC, Apartado 3004, 18080 Granada, Spain
Gabriel, Maurice ; Département d'astrophys., géophysique et océanographie (AGO)
Scuflaire, Richard ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Evol. et stabilité des étoiles et des amas d'étoiles (ESEA)
Language :
English
Title :
Convection-pulsation coupling. II. Excitation and stabilization mechanisms in delta Sct and gamma Dor stars
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