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arXiv · 1102.0150

Comprehensive study of the magnetic stars HD 5797 and HD 40711 with large chromium and iron overabundances

E. A. Semenko·I. A. Yakunin·E. Yu. Kuchaeva
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Abstract

We present the results of a comprehensive study of the chemically peculiar stars HD 5797 and HD 40711. The stars have the same effective temperature, Teff = 8900 K, and a similar chemical composition with large iron (+1.5 dex) and chromium (+3 dex) overabundances compared to the Sun. The overabundance of rare-earth elements typically reaches +3 dex. We have measured the magnetic field of HD 5797. The longitudinal field component Be has been found to vary sinusoidally between -100 and +1000 G with a period of 69 days. Our estimate of the evolutionary status of the stars suggests that HD 5797 and HD 40711, old objects with an age t \approx 5 \times 108 yr, are near the end of the core hydrogen burning phase.

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E. A. Semenko, I. A. Yakunin, E. Yu. Kuchaeva. 2011-02-01. Comprehensive study of the magnetic stars HD 5797 and HD 40711 with large chromium and iron overabundances. https://doi.org/10.1134/s1063773710121023

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