New magnetic cataclysmic variable detected

INA - SOURCES 

Spacecraft and the Transiting Exoplanet Survey Satellite (TESS) astronomers have detected a new magnetic cataclysmic variable. 

The new object, designated SRGE J075818-612027, is most likely of the polar subtype. The finding was reported in a paper published February 26 on the pre-print server arXiv.

Cataclysmic variables (CVs) are binary star systems consisting of a white dwarf accreting material from a normal star companion. They irregularly increase in brightness by a large factor, then drop back down to a quiescent state. Polars are a subclass of cataclysmic variables distinguished from other CVs by the presence of a very strong magnetic field in their white dwarfs.

Recently, a team of astronomers led by Samet Ok of the Leibniz Institute for Astrophysics Potsdam (AIP) in Germany, has analyzed observational data of the field of open cluster NGC 2516 using Spektr-RG's eROSITA X-ray telescope and TESS. As a result, they serendipitously discovered a new CV.

"We report the discovery of SRGE J075818-612027, a deep stream-eclipsing magnetic cataclysmic variable found serendipitously in SRG/eROSITA CalPV observations of the open cluster NGC 2516 as an unrelated X-ray source," the researchers wrote in the paper.

SRGE J075818-612027 was identified as one of the X-ray brightest objects of the field during the eROSITA Calibration and Performance Verification (CalPV) phase of observations. It turned out to be an accretion-powered background object at a distance of between 4,000 and 13,500 light years.