Exploring the effects of detailed chemical profiles on the adiabatic oscillation spectrum of sdB stars: First Results

We present results of an ongoing study of the pulsational properties of sdB stellar models aimed at exploring the consequences of detailed chemical transitions for radial, $p-$ and $g-$ modes. In particular, we focus on the effects of diffusion at the H-He transition and of He-burning at the convective cores. We find that diffusion of He and H has a strong impact on the period spectrum of sdBVs stars, leading to less efficient mode trapping. Our results also suggests that asteroseismology of sdBVs stars might offer a very good opportunity to constrain extramixing processes in the He-burning cores of horizontal branch stars.