Rotation and convective core overshoot in theta Ophiuchi

Abstract

International audienceContext. Recent work on several beta Cephei stars has succeeded in constraining both their interior rotation profile and their convective core overshoot. In particular, a recent study focusing on theta Ophiuchi has shown that a convective core overshoot parameter of alpha_ov = 0.44 is required to model the observed pulsation frequencies, significantly higher than for other stars of this type. Aims: We investigate the effects of rotation and overshoot in early type main sequence pulsators, such as beta Cephei stars, and attempt to use the low order pulsation frequencies to constrain these parameters. This will be applied to a few test models and the beta Cephei star theta Ophiuchi. Methods: We use the 2D stellar evolution code ROTORC and the 2D linear adiabatic pulsation code NRO to calculate pulsation frequencies for 9.5 M&sun; models evolved to an age of 15.6 Myr. We calculate low order p-modes (