Towards stellar seismology of massive pulsators with the CoRoT and Kepler satellites

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Asteroseismology, the study of stellar oscillations, is the only way to probe the internal structure of stars and significantly improve our understanding of stellar evolution. By measuring stellar pulsation frequencies and other oscillation mode parameters through light and spectral variations, one can constrain the physical properties of stellar interiors. Asteroseismic studies of more massive stars than the Sun are in particular important as these stars have a different internal structure and are the progenitors of objects that will finally enrich their environment with heavy metals, and hence rule galactic evolution. The pulsation mode selection mechanism in massive stars is not yet fully understood, and must depend on a combination of non-linear effects between rotation and convection. Only a systematic asteroseismic study of a large number of pulsating stars, and hence putting constraints on the internal properties, allows to solve this open question in astrophysics. Thanks to the recently launched space missions CoRoT and Kepler, that are providing excellent photometric time-series for thousands of pulsating stars, it is being possible to investigate for the first time the pulsational behaviour of a large enough sample of each pulsation class. With this project we will study with CoRoT and Kepler pulsators of the not-well understood class of γ Dor stars (Spectral Type A-F, M=1.2-2.5M⊙). We will model the targets, constrain the pulsation mechanism, and arrive at a first reliable seismic description of this class of pulsators.