[en] We investigate how the frequencies of gravity modes depend on the detailed properties of the chemical composition gradient that develops near the core of main-sequence stars and, therefore, on the transport processes that are able to modify the \mu profile in the central regions. We show that in main-sequence models, similarly to the case of white dwarfs, the periods of high-order gravity modes are accurately described by a uniform period spacing superposed to an oscillatory component. The periodicity and amplitude of such a component are related, respectively, to the location and sharpness of the \mu gradient. We briefly discuss and interpret, by means of this simple approximation, the effect of turbulent mixing near the core on the periods of both high-order and low-order g modes, as well as of modes of mixed pressure-gravity character.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Miglio, Andrea ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie
Montalban Iglesias, Josefa ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie
Eggenberger, P.; Institut d'Astrophysique et de Géophysique de l'Université de Liège, Allée du 6 Août, 17 B-4000 Liège, Belgium
Noels-Grötsch, Arlette ; Institut d'Astrophysique et de Géophysique de l'Université de Liège, Allée du 6 Août, 17 B-4000 Liège, Belgium
Language :
English
Title :
Gravity modes and mixed modes as probes of stellar cores in main-sequence stars: From solar-like to β Cep stars
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