The acoustic spectrum of alpha Cen A

This paper presents the analysis of Doppler p-mode observations of the G2V star a 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 ms 0 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 μHz. A comparison with stellar models of a Cen A is presented.

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