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arXiv · 1508.06298

FS CMa type binaries

Anatoly Miroshnichenko·Sergey Zharikov
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Abstract

FS CMa type stars is a group of ~70 objects formerly known as unclassified stars with the B[e] phenomenon. Their very strong emission-line spectra in combination with a nearly main-sequence luminosity suggest the binary nature for them. They possess strong IR excesses due to radiation of circumstellar dust that implies a compact distribution probably in a circumbinary disk. Our long-term spectroscopic monitoring revealed neutral metal lines, which always include that of Li I 6708 Å, in the spectra of some FS CMa objects indicating the presence of a cool star. We present a summary of our results with a first overview of FS CMa type binaries and review possible implications for the nature and evolutionary status of the entire group.

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Anatoly Miroshnichenko, Sergey Zharikov. 2015-08-25. FS CMa type binaries. https://doi.org/10.1051/eas%2F1571040

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