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arXiv · 1906.06984

Statistical analysis of roAp, He-weak and He-rich stars

S. Ghazaryan·G. Alecian·A. A. Hakobyan
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Abstract

To enlarge our database of Chemically Peculiar (CP) stars, we compiled published data concerning the He-weak and He-rich stars observed by high-resolution spectroscopy techniques during last decades. Twenty He-weak and 28 He-rich stars have been added to the database. We have also distinguished roAp stars from stars previously identified as Ap stars. To deepen our knowledge on statistical overview of the abundance anomalies versus the physical parameters of stars, we compared our data with previous compilations. We applied statistical tests on our data and found interesting correlations for effective temperature and surface gravity for all type of stars and a few correlations for projected rotation velocity only for He-rich stars. Because of the lack of the data we couldn't check whether being a member of binary system is affecting on chemical peculiarities of those stars.

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S. Ghazaryan, G. Alecian, A. A. Hakobyan. 2019-06-17. Statistical analysis of roAp, He-weak and He-rich stars. https://doi.org/10.1093/mnras%2Fstz1678

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