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Radial Velocity Variations in Pulsating Ap Stars III. The Discovery of 16.21 min Oscillations in Beta CrB

Artie P. Hatzes·David E. Mkrtichian
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Abstract

We present the analysis of 3 hrs of a rapid time series of precise stellar radial velocity (RV) measurements (sigma = 4.5 m/s) of the cool Ap star Beta CrB. The integrated RV measurements spanning the wavelength interval 5000-6000 Ang. show significant variations (false alarm probability = 10^-5) with a period of 16.21 min (nu = 1028.17 micro Hz) and an amplitude of 3.54 +/- 0.56 m/s. The RV measured over a much narrower wavelength interval reveals one spectral feature at 6272 Ang. pulsating with the same 16.21 min period and an amplitude of 138 +/- 23 m/s. These observations establish Beta CrB to be a low-amplitude rapidly oscillating Ap star.

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Artie P. Hatzes, David E. Mkrtichian. 2004-03-10. Radial Velocity Variations in Pulsating Ap Stars III. The Discovery of 16.21 min Oscillations in Beta CrB. https://doi.org/10.1111/j.1365-2966.2004.07816.x

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