CQ UMa – a slowly accelerating cool magnetic CP star
| Main Authors: | Mikulasek, Zdenek, Janik, Jan, Krticka, Jiri, Zejda, Miloslav, Paunzen, Ernst, Romanyuk, Iosif, Yakunin, Ilya, Hummerich, Stefan, Bernhard, Klaus, David-Uraz, Alexandre, Shultz, Matthew |
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| Format: | info Proceeding Journal |
| Bahasa: | eng |
| Terbitan: |
, 2021
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/5040838 |
Daftar Isi:
- CQ UMa = HD 119213 is a member of an exclusive SrCrEu star club showing significant variability in the c1 index, expressing the Balmer jump's height. The cause of the light variability of those cool mCP stars is not yet known. The group includes, e.g., CS Vir, VV Scl, BR Cru, and BS Cir, which is known to change its period. We are preparing a comprehensive study of these stars, most of which have sufficiently high-quality TESS photometry. 58954 individual photometric, spectroscopic, and magnetic observations of CQ UMa obtained during the last 50 years helped us reveal a marginal acceleration of its rotation period as $\dot{P}=10(3)\times10^{-10}$, which is by far the slightest proven period change in mCPs. The case of CQ UMa suggests that the rotation period variability affects all types and mass categories of mCP stars and may not be as rare as we thought so far.