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arXiv · 2611.07448

Systematic Search for Cataclysmic Variables in Radio Surveys: First Radio Detection of IX Velorum

Suhasini S. Rao·Gregory R. Sivakoff·Craig O. Heinke·Akash Anumarlapudi·Laura Driessen·David L. Kaplan Patrick A. Woudt
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Abstract

We present a systematic search for radio emission from cataclysmic variables (CVs) across four wide-field radio surveys in the 0.7-4 GHz frequency range: VLASS; RACS; VAST; and EMU. We generated a reliable catalog of 2225 optically-identified CV candidates using a multi-stage cross-match, combined with systematic and manual verification; 1374 are matched to Gaia sources within the radio surveys' footprints. Among these, we detected six CVs in at least one epoch (at 1e16.5-1e17.5 erg/s/Hz, consistent with the typical population of radio-detected CVs); five had been detected in radio before. IX Vel, the closest nova-like CV, is detected in radio for the first time and shows quasi-persistent low-level emission across a 10 hr EMU (943.5 MHz) observation. Given most epochs detected no CV, we stacked images without radio detections to better constrain time-averaged brightnesses. We created co-added images and placed upper limits on low-level radio emission from each of the 423 individual CVs within the VAST footprint. To constrain the median brightness for the entire CV population, we combined all Gaia-matched CVs in each survey into single population-wide stacked images, detecting no statistically significant emission. Finally, we created population-wide image stacks of the CVs within 100 pc, using 14 epochs from 5 CVs in EMU to constrain their median persistent specific luminosity to <3e14 erg/s/Hz.

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Suhasini S. Rao, Gregory R. Sivakoff, Craig O. Heinke, Akash Anumarlapudi, Laura Driessen, David L. Kaplan Patrick A. Woudt. 2026-11-05. Systematic Search for Cataclysmic Variables in Radio Surveys: First Radio Detection of IX Velorum. https://arxiv.org/abs/2611.07448

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