Institut national de recherche scientifique français Univerité Pierre et Marie Curie Université Paris Diderot - Paris 7

Importance of radiative accelerations for the transport of chemical elements in main-sequence stars

mardi 27 novembre 2018, par Morgan Deal (LESIA)

Mardi 11 dĂ©cembre 2018 à 11h00 , Lieu : Salle de confĂ©rence du bâtiment 17

Atomic diffusion, including the effect of radiative accelerations on individual elements, leads to variations of the chemical composition inside the stars as well as the surface abundances evolution. Indeed the accumulation in specific layers of the elements, which are the main contributors of the local opacity, modifies the internal stellar structure and surface abundances. Here we show that the variations of the chemical composition induced by atomic diffusion in G and F type stars can have significant impact on their structure, stellar parameters and seismic properties. We will also discuss the effect of the coupling between rotation and atomic diffusion for such stars. These processes need to be taken into account in stellar evolution models as the observations are more and more precise, especially in the context of the space missions TESS and PLATO.