1999A&A...350..617B

The aim of this paper is to discuss the possible stellar origin of the observed excess power presented in Martic et al. (1999, A+A, accepted) by comparing these observational data with theoretical predictions and numerical simulations. Stellar models are calculated for Procyon A with appropriate physics for this star and with the revised astrometric mass (1.46±0.04)M_☉ found by Girard (1998, priv. comm.). For these models, we compute the expected oscillation spectra for l=0,1,2 modes including m{!0 according }to theoretical amplitude predictions. Time-series are then simulated, in the same conditions as the observations, and compared by Fourier analysis with the observed ones. We show that the characteristics of the signal are in good agreement with what should be expected for such observing runs and we emphasize the importance of obtaining multi-site observations for this star. We confirm the presence of a periodic pattern in the Fourier spectrum, this pattern being interpreted as the so-called large separation.