UGPS J194310+183851: an Unusual Optical and X-ray Faint Cataclysmic Variable?

Abstract

The growing number of multi-epoch optical and infrared sky surveys are uncovering unprecedented numbers of new variable stars, of an increasing number of types. The short interval between observations in adjacent near infrared filters in the UKIDSS Galactic Plane Survey (UGPS) allows for the discovery of variability on the timescale of minutes. We report on the nature of one such object, through the use of optical spectroscopy, time-series photometry and targeted X-ray observations. We propose that UGPS J194310.32+183851.8 is a magnetic cataclysmic variable star of novel character, probably featuring a longer than average spin period and an orbital period likely to be shorter than the period gap (i.e. P${}_{\text{orb}}$<2 hours). We reason that the star is likely a member of the short period Intermediate-Polar subclass that exist below this period boundary, but with the additional feature that system's SED is fainter and redder than other members of the group.

9 pages, 9 figures

References in corpus (16)

• The Gaia mission
• Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
• The UKIDSS Galactic Plane Survey
• The VST Photometric Halpha Survey of the Southern Galactic Plane and Bulge (VPHAS+)
• VIRAC: The VVV Infrared Astrometric Catalogue
• The origin and evolution of magnetic white dwarfs in close binary stars
• The Accretion Flows and Evolution of Magnetic Cataclysmic Variables
• Constraints on the space density of intermediate polars from the Swift-BAT survey
• Time-resolved optical observations of five cataclysmic variables detected by INTEGRAL
• A comparative study of the strength of flickering in cataclysmic variables
• Extreme infrared variables from UKIDSS - II. an end-of-survey catalogue of eruptive YSOs and unusual stars
• SDSS J233325.92+152222.1 and the evolution of intermediate polars
• XMM-Newton observations of the complex spin pulse of the intermediate polar PQ~Geminorum
• Exploratory Spectroscopy of Magnetic Cataclysmic Variables Candidates and Other Variable Objects
• Quasi-periodic oscillations in the TESS light curve of TX Col, a diskless intermediate polar on the precipice of forming an accretion disk
• XMM-Newton and Optical Observations of Cataclysmic Variables from SDSS