Discovery of eRASSt J192932.9-560346: A bright, two-pole accreting, eclipsing polar

Schwope A, Buckley DAH, Malyali A, Potter S, König O, Arcodia R, Gromadzki M, Rau A (2022)


Publication Type: Journal article

Publication year: 2022

Journal

Book Volume: 661

DOI: 10.1051/0004-6361/202141653

Abstract

We report the discovery of a bright (V similar to 15), eclipsing, two-pole accreting magnetic cataclysmic variable (CV), a polar, as counterpart of the SRG/eROSITA and Gaia transients eRASStJ192932.9-560346 and Gaia21bxo. Frequent large-amplitude changes of its brightness at X-ray and optical wavelengths by more than four magnitudes are indicative of a CV nature of the source. Identification spectra obtained with the 10m SALT telescope revealed the typical features of a magnetic CV: strong, broad HeI, HeII, and hydrogen Balmer emission lines superposed on a blue continuum. Time-resolved photoelectric polarimetry revealed that the circular polarization varies from -20 to +20% and the linear polarization varies from 0 to 10%, confirming the system to be a magnetic CV of the polar subclass. High-cadence photometry revealed deep, structured eclipses, indicating that the system is a two-pole accretor. The orbital period determined from the eclipse times is 92.5094 +/- 0.0002 min. The X-ray spectrum is thermal only, and the implied luminosity is L-X = 2.2 x 10(31) erg s(-1) at the Gaia-determined distance of 376 pc.

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APA:

Schwope, A., Buckley, D.A.H., Malyali, A., Potter, S., König, O., Arcodia, R.,... Rau, A. (2022). Discovery of eRASSt J192932.9-560346: A bright, two-pole accreting, eclipsing polar. Astronomy & Astrophysics, 661. https://doi.org/10.1051/0004-6361/202141653

MLA:

Schwope, Axel, et al. "Discovery of eRASSt J192932.9-560346: A bright, two-pole accreting, eclipsing polar." Astronomy & Astrophysics 661 (2022).

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