Sounding the cores of stars by gravity-mode asteroseismology

Asteroseismology is a recent branch of astrophysics that studies the interiors of stars by the interpretation of their pulsation spectra. A wide variety of stars exhibit pulsations, including gravity-modes (driven by buoyancy) that usually penetrate deep inside the stars. By probing these deep layers unreachable from classical observations, the g-mode oscillations bring invaluable information for stellar evolution and astrophysics in general.

I will illustrate in my talk the power of g-mode asteroseismology by the example of Extreme Horizontal Branch stars, that are on an intermediate stage of evolution, and show how g-modes allow us to determine the properties of the cores in these stars, including their convective characteristics, size and composition.