The acoustic spectrum of alpha Cen A

This paper presents the analysis of Doppler p-mode observations of the G2V star $\alpha$ Cen A obtained with the spectrograph CORALIE in May 2001. Thirteen nights of observations have made it possible to collect 1850 radial velocity measurements with a standard deviation of about 1.5 m s${}^{-1}$. Twenty-eight oscillation modes have been identified in the power spectrum between 1.8 and 2.9 mHz with amplitudes in the range 12 to 44 cm s${}^{-1}$. The average large and small spacing are respectively equal to 105.5 and 5.6 $\mu$Hz. A comparison with stellar models of $\alpha$ Cen A is presented.