Publication details

Ap stars with variable periods

Authors

MIKULÁŠEK Zdeněk KRTIČKA Jiří JANÍK Jaroslav ZEJDA Miloslav HENRY Gregory PAUNZEN Ernst ŽIŽNOVSKÝ Jozef ZVERKO Juraj

Year of publication 2014
Type Article in Proceedings
Conference Putting A Stars into Context: Evolution, Environment, and Related Stars
MU Faculty or unit

Faculty of Science

Citation
Web https://arxiv.org/pdf/1310.6640.pdf
Field Astronomy and astrophysics
Keywords stars:peculiar; stars
Description The majority of magnetic chemically peculiar (mCP) stars exhibit periodic light, magnetic, radio, and spectroscopic variations that can be modelled adequately as a rigidly-rotating main-sequence star with persistent surface structures. Nevertheless, there is a small sample of diverse mCP stars whose rotation periods vary on timescales of decades while the shapes of their phase curves remain unchanged. Alternating period increases and decreases have been suspected in the hot CP stars CU Vir and V901 Ori, while rotation in the moderately cool star BS Cir has been decelerating. These examples bring new insight into this theoretically unpredicted phenomenon. We discuss possible causes of such behaviour, and propose that dynamic interactions between a thin, outer, magnetically-confined envelope braked by the stellar wind, and an inner faster-rotating stellar body, are able to explain the observed rotational variability.
Related projects:

You are running an old browser version. We recommend updating your browser to its latest version.

More info