The Seismology of Stars
Abstract
Until recently, the great steps of stellar evolution have been studied only theoretically. This allowed to account for the observations of stellar surfaces. However many problems prove that the formalism is not complete: evolution of young stars, the problem of solar neutrinos, the burning of lithium, the origin of stellar winds, ultimate stages of stellar evolution... Often these open problems are linked to theoric limitations of the framework, which does not account for internal dynamics. Stellar seismology is a discipline which will contribute to change this situation while penetrating judiciously in the stellar interior. Thanks to the ground networks and SOHO satellite, the heliosismology has already revealed the internal dynamics of the Sun and has transformed this banal star into a true cosmic physics laboratory. The quality of the observations is also a formidable challenge for the theoricians who could validate their assumptions when the terrestrial laboratory remained impotent. I will show that confirming the complex physics included in the models is today an accomplished task, from the center of the Sun until its surface, with a precision of a few percent. But still more interesting, we begin to introduce the effects of rotation and of magnetic field, tackling today the dynamic processes which connect the stellar interior to the eruptive processes. This opens the gate to a three-dimensional representation of stars and to a better understanding of galactic enrichment or of the role of our star in our daily environment. However the Sun cannot, alone, account for the history of stellar angular momentum or of all stellar energetic phenomena. It is essential to extend this effort to a great number of samples, therefore I will show how this is possible and what we expect from asterosismology projects such as COROT or EDDINGTON.
- Publication:
-
SF2A-2001: Semaine de l'Astrophysique Francaise
- Pub Date:
- May 2001
- Bibcode:
- 2001sf2a.conf..101T