Oscillation power as a diagnostic tool for stellar turbulent spectra

Abstract

Recent observations and theoretical studies support the theory that solar-type oscillations are intrinsically stable but excited stochastically by the turbulent convection in the outer layers of the star. The acoustic noise generated by the convective motion depends on the details of the turbulent energy spectrum. In this paper we present a general formulation for the acoustic noise generation rate based on previous works by other authors. In this general formulation any model for the spatial turbulent energy spectrum and for the turbulent time spectrum can be assumed. We compute acoustic power spectra and oscillation amplitudes of radial oscillations for models of the Sun and Procyon A. The results are compared with recent observations.