P - mode observations on α Cen A ⋆
نویسنده
چکیده
We have made a clear detection of p-mode oscillations in the nearest solar-like G2V star α Cen A with the CORALIE spectrograph on the 1.2-m Swiss telescope at the ESO La Silla Observatory. We report the 5 nights of observation on this star in May 2001 during which 1260 high precision radial velocity measurements were obtained. The power spectrum clearly shows several identifiable peaks between 1.7 and 3 mHz. The average large splitting of 105.7 μHz and the amplitude of about 35 cm s of these modes are in agreement with theoretical expectations.
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تاریخ انتشار 2001