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The acoustic spectrum of alpha Cen A

F. Bouchy·F. Carrier
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Abstract

This paper presents the analysis of Doppler p-mode observations of the G2V star $α$ 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 $μ$Hz. A comparison with stellar models of $α$ Cen A is presented.

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F. Bouchy, F. Carrier. 2002-06-04. The acoustic spectrum of alpha Cen A. https://doi.org/10.1051/0004-6361%3A20020706

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