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arXiv · 2011.01312

Superfast Line Profile Variations in the Spectra of OBA Stars III: A0 Star $\alpha^2\,$CVn, New Results

A. F. Kholtygin·A. V. Moiseeva·I A. Yakunin·S. Hubrig
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Abstract

This work is a continuation of the studies of the ultrafast variability of line profiles in the spectra of early-type stars. Line profile variations (LPVs) in the spectrum a chemically peculiar A0Vp star $\alpha^2\,$CVn are investigated using the January 6, 2020 observations carried out with the 6-meter BTA telescope at Special Astrophysical observatory (SAO) of the Russian Academy of Sciences (RAS) equipped with the MSS spectrograph. Regular short-term periodic variations of the H$_\beta$, Fe\,II, and Cr\,II lines were detected with periods ranging from $\sim\!$4 to $\sim\!$140 minutes. The magnetic field of the star was determined for all observations. The average measured longitudinal magnetic field component over the entire duration of observations is about $\approx$600\,G, which is close to the value expected from the well-known magnetic field phase curve.

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A. F. Kholtygin, A. V. Moiseeva, I A. Yakunin, S. Hubrig. 2020-11-02. Superfast Line Profile Variations in the Spectra of OBA Stars III: A0 Star $\alpha^2\,$CVn, New Results. https://doi.org/10.1134/s1990341320030086

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