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Title: MACHO 311.37557.169: A VY Scl star
Abstract

Optical surveys, such as the MACHO project, often uncover variable stars whose classification requires follow‐up observations by other instruments. We performed X‐ray spectroscopy and photometry of the unusual variable star MACHO 311.37557.169 withXMM‐Newtonin April 2018, supplemented by archival X‐ray and optical spectrographic data. The star has a bolometric X‐ray luminosity of about 1 × 1032 erg s−1 cm−2and 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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PAR ID:
10156492
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Astronomische Nachrichten
Volume:
341
Issue:
3
ISSN:
0004-6337
Page Range / eLocation ID:
p. 283-290
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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