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arXiv · 2503.23838

A MeerKAT survey of nearby dwarf novae: I. New detections

J. Kersten·E. Körding·P. A. Woudt·P. J. Groot·D. R. A. Williams·I. Heywood·D. L. Coppejans·C. Knigge·J. C. A. Miller-Jones·G. R. Sivakoff·R. Fender
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Abstract

A program to search for radio emission from dwarf-novae-type cataclysmic variables was conducted with the South African MeerKAT radio telescope. The dwarf novae RU Pegasi, V426 Ophiuchi and IP Pegasi were detected during outburst at L-band (1284 MHz central frequency). Previously, only one cataclysmic variable was radio-detected at a frequency this low. We now bring the number to four. With these three newly found radio-emitters, the population of dwarf novae confirmed to be radio-emitting at any frequency reaches 10 systems. We found that the radio luminosity is correlated with the optical luminosity. For V426 Ophiuchi and RU Pegasi we found a radio decline contemporary with the outburst's optical decline. The peak radio luminosity of dwarf novae in outburst is very similar to that of novalike Cataclysmic Variables and no correlation with orbital period is seen.

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J. Kersten, E. Körding, P. A. Woudt, P. J. Groot, D. R. A. Williams, I. Heywood, D. L. Coppejans, C. Knigge, J. C. A. Miller-Jones, G. R. Sivakoff, R. Fender. 2025-03-31. A MeerKAT survey of nearby dwarf novae: I. New detections. https://doi.org/10.1093/mnras%2Fstaf556

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