Solar-like oscillations in massive main-sequence stars

I. Asteroseismic signatures of the driving and damping regions

Institut d'Astrophysique et de Géophysique, Université de Liège, Allée du 6 Août 17, 4000 Liège, Belgium e-mail: Kevin.Belkacem@obspm.fr

Received: 31 August 2009
Accepted: 27 October 2009

Abstract

Motivated by the detection of stochastically excited modes in the massive star V1449 Aql, which is already known to be a β Cephei star, we theoretically investigate the driving by turbulent convection. By using a full non-adiabatic computation of the damping rates, together with a computation of the energy injection rates, we provide an estimate of the amplitudes of modes excited by both the convective region induced by the iron opacity bump and the convective core. Despite the uncertainties in the dynamical properties of these convective regions, we demonstrate that both regions are able to efficiently excite p modes above the CoRoT observational threshold and the solar amplitudes. In addition, we emphasise the potential asteroseismic diagnostics provided by each convective region, which we hope will help us to identify the region responsible for solar-like oscillations, and to place constraints on this convective zone. A forthcoming work will be dedicated to an extended investigation of the likelihood of solar-like oscillations across the Hertzsprung-Russell diagram.