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arXiv · 1811.08049

Quest for the Donor Star in the Magnetic Precataclysmic Variable V1082 Sgr

G. Tovmassian·J. F. Gonzalez·M. -S. Hernandez·D. Gonzalez-Buitrago·S. Zharikov·J. V. Hernandez Santisteban
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Abstract

We obtained high-resolution spectra and multicolor photometry of V1082 Sgr to study the donor star in this 20.8 hr orbital period binary, which is assumed to be a detached system. We measured the rotational velocity (v sin i = 26.5+/-2.0 km/s), which, coupled with the constraints on the white dwarf mass from the X-ray spectroscopy, leads to the conclusion that the donor star barely fills 70% of its corresponding Roche lobe radius. It appears to be a slightly evolved K2-type star. This conclusion was further supported by a recently published distance to the binary system measured by the Gaia mission. At the same time, it becomes difficult to explain a very high (> 10e-9 Msun/yr) mass transfer and mass accretion rate in a detached binary via stellar wind and magnetic coupling.

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G. Tovmassian, J. F. Gonzalez, M. -S. Hernandez, D. Gonzalez-Buitrago, S. Zharikov, J. V. Hernandez Santisteban. 2018-11-20. Quest for the Donor Star in the Magnetic Precataclysmic Variable V1082 Sgr. https://doi.org/10.3847/1538-4357/aaec02

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