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arXiv · 2003.06896

MACHO 311.37557.169: A VY Scl star

H. Worpel·A. D. Schwope·I. Traulsen·M. J. I. Brown
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Abstract

Optical surveys, such as the MACHO project, often uncover variable stars whose classification requires followup observations by other instruments. We performed X-ray spectroscopy and photometry of the unusual variable star MACHO 311.37557.169 with \XMM\ in April 2018, supplemented by archival X-ray and optical spectrographic data. The star has a bolometric X-ray luminosity of about $1\times 10^{32}$ erg s$^{-1}$ cm$^{-2}$ and a heavily absorbed two-temperature plasma spectrum. The shape of its light curve, its overall brightness, its X-ray spectrum, and the emission lines in its optical spectrum suggest that it is most likely a VY~Scl cataclysmic variable.

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H. Worpel, A. D. Schwope, I. Traulsen, M. J. I. Brown. 2020-03-15. MACHO 311.37557.169: A VY Scl star. https://doi.org/10.1002/asna.202013531

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