Radio detections of two unusual cataclysmic variables in the VLA Sky Survey
arXiv:2303.01438 · doi:10.1093/mnras/stad038
Abstract
We report two new radio detections of cataclysmic variables (CVs), and place them in context with radio and X-ray detections of other CVs. We detected QS Vir, a low accretion-rate CV; V2400 Oph, a diskless intermediate polar (IP); and recovered the polar AM Her in the Very Large Array Sky Survey (VLASS) 2-4 GHz radio images. The radio luminosities of these systems are higher than typically expected from coronal emission from stars of similar spectral types, and neither system is expected to produce jets, leaving the origin of the radio emission a puzzle. The radio emission mechanism for these two CVs may be electron-cyclotron maser emission, synchrotron radiation, or a more exotic process. We compile published radio detections of CVs, and X-ray measurements of these CVs, to illustrate their locations in the radio - X-ray luminosity plane, a diagnostic tool often used for X-ray binaries, active galactic nuclei, and radio stars. Several radio-emitting CVs, including these two newly detected CVs, seem to lie near the principal radio/X-ray track followed by black hole X-ray binaries (BHXBs) at low luminosity, suggesting additional complexity in classifying unknown systems using their radio and X-ray luminosities alone.
References in corpus (23)
- Estimating distances from parallaxes. V: Geometric and photogeometric distances to 1.47 billion stars in Gaia Early Data Release 3
- Second ROSAT all-sky survey (2RXS) source catalogue
- The XMM-Newton serendipitous survey IX. The fourth XMM-Newton serendipitous source catalogue
- Confirmation of the Electron Cyclotron Maser Instability as the Dominant Source of Radio Emission from Very Low Mass Stars and Brown Dwarfs
- A radio pulsing white dwarf binary star
- The radio/X-ray domain of black hole X-ray binaries at the lowest radio luminosities
- The Deep SWIRE Field I. 20cm Continuum Radio Observations: A Crowded Sky
- A transient radio jet in an erupting dwarf nova
- Polarimetric evidence of a white dwarf pulsar in the binary system AR Scorpii
- Disk-jet coupling in low-luminosity accreting neutron stars
- Dwarf nova-type cataclysmic variable stars are significant radio emitters
- Hunting high and low: XMM monitoring of the eclipsing polar HU Aquarii
- The MAVERIC Survey: Chandra/ACIS Catalog of Faint X-ray sources in 38 Galactic globular clusters
- XMM-Newton observations of EF Eridani: the textbook example of low-accretion rate polars
- Rapid Radio Flaring during an Anomalous Outburst of SS Cyg
- Quasi-periodic oscillations in the TESS light curve of TX Col, a diskless intermediate polar on the precipice of forming an accretion disk
- Follow-up Studies of Five Cataclysmic Variable Candidates Discovered by LAMOST
- Driving the Beat: Time-Resolved Spectra of the White Dwarf Pulsar AR Scorpii
- A MeerKAT Survey of Nearby Novalike Cataclysmic Variables
- Radio and optical observations of the possible AE Aqr twin, LAMOST J024048.51+195226.9
- Non-thermal radio continuum emission from young nearby stars
- Optical spectra of FO Aquarii during low and high accretion rates
- Searching for Diamagnetic Blob Accretion in the 74 day K2 Observation of V2400 Ophiuchi