Radio emission from Cataclysmic Variables: new insights from 5 years of MeerKAT observations

Over the past 5 years, the ThunderKAT large survey project on MeerKAT has observed a representative sample of nearby Cataclysmic Variables (CVs); accreting white dwarfs in close compact binaries. Dwarf novae are non-magnetic CVs that display periodic outbursts due to a thermal-viscous instability in the accretion disk, leading to short periods (days to weeks) of enhanced mass transfer onto the white dwarf. Whilst these systems are the dominant population in optical transient surveys, their radio emission is inherently faint and remains poorly understood. ThunderKAT has quadrupled the number of dwarf novae detected at L-band during outburst, all showing repeatable behaviour across multiple outbursts in both L-band and S-band. In the first part of this talk I will give an overview of the main results from the CV component of ThunderKAT and highlight the new insights gained from 5 years of MeerKAT observations. 

The unique capability of MeerKAT to study accreting white dwarfs in compact binaries across a range of time-scales (seconds to years) is further demonstrated by the remarkable MeerKAT observation of narrow pulsed emission from the second known white dwarf pulsar, J1912-4410. This is the first white dwarf to show pulsar-like narrow pulsed emission at radio frequencies, akin to neutron star pulsars. This system is thought to represent an evolutionary stage in accreting magnetic CVs. In the second part of this talk I will present the MeerKAT observations of J1912-4410 -- a white dwarf pulsar in a compact binary -- and discuss the potential of fast (2-sec) commensal imaging searches with MeerKAT to unveil additional white dwarf pulsars in the Milky Way.