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arXiv · 1311.1943

Spectropolarimetric study of the classical Cepheid $\eta$ Aql: pulsation and magnetic field

V. Butkovskaya·S. Plachinda·D. Baklanova·V. Butkovskyi
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Abstract

We report the results of spectropolarimetric study of the classical Cepheid $\eta$ Aql. We found that the longitudinal magnetic field of $\eta$ Aql sinusoidally varies with the radial pulsation period, while the amplitude $B$, mean field $B_0$, and phases of maximum and minimum field change from year to year. We hypothesize that possible reasons of those variations are stellar axial rotation or dynamo mechanisms.

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V. Butkovskaya, S. Plachinda, D. Baklanova, V. Butkovskyi. 2013-11-08. Spectropolarimetric study of the classical Cepheid $\eta$ Aql: pulsation and magnetic field. https://doi.org/10.1017/s1743921313014713

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