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We present 8--12\,GHz radio light curves of five dwarf nova (DN) type Cataclysmic Variable stars (CVs) in outburst (RX And, U Gem and Z Cam), or superoutburst (SU UMa and YZ Cnc), increasing the number of radio-detected DN by a factor of…

Radio emission from non-magnetic cataclysmic variables (CVs, accreting white dwarfs) could allow detailed studies of outflows and possibly accretion flows in these nearby, numerous and non-relativistic compact accretors. Up to now, however,…

Accreting white dwarfs in binary systems known as cataclysmic variables (CVs) have in recent years been shown to produce radio flares during outbursts, qualitatively similar to those observed from neutron star and black hole X-ray binaries,…

High Energy Astrophysical Phenomena · Physics 2019-10-09 Rob Fender , Joe Bright , Kunal Mooley , James Miller-Jones

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…

The Jansky Very Large Array was used to observe 121 magnetic cataclysmic variables (MCVs). We report radio detections of 19 stars. Fourteen are new radio sources, increasing the number of MCVs that are radio sources by more than twofold,…

Solar and Stellar Astrophysics · Physics 2017-12-06 Paul E. Barrett , Christopher Dieck , Anthony J. Beasley , Kulinder P. Singh , Paul A. Mason

The NSF's Karl G. Jansky Very Large Array (VLA) is used to observe 122 magnetic cataclysmic variables (MCVs) during three observing semesters (13B, 15A, and 18A). We report radio detections of 33 stars with fluxes in the range 6--8031 uJy.…

Solar and Stellar Astrophysics · Physics 2020-06-16 Paul Barrett , Christopher Dieck , Anthony J. Beasley , Paul A Mason , Kulinder P. Singh

Two coherent radio emission mechanisms operate in stellar coronae: plasma emission and cyclotron emission. They directly probe the electron density and magnetic field strength respectively. Most stellar radio detections have been made at…

Solar and Stellar Astrophysics · Physics 2020-11-11 H. K. Vedantham

We report the detection of periodic (p = 1.96 hours) bursts of extremely bright, 100% circularly polarized, coherent radio emission from the M9 dwarf TVLM 513-46546. Simultaneous photometric monitoring observations have established this…

We study the variability of the cataclysmic variable DO Dra, on time-scales of between minutes and decades. The characteristic decay time dt/dm=0.902(3) days/mag was estimated from our 3 nights of CCD R observations. The quiescent data show…

Astrophysics · Physics 2008-06-13 I. L. Andronov , L. L. Chinarova , W. Han , Y. Kim , J. -N. Yoon

Recent results are presented and discussed regarding the EUV and X-ray emission of nonmagnetic cataclysmic variables. Emphasis is given to high accretion rate systems (novalike variables and dwarf novae in outburst), and to a number of…

Astrophysics · Physics 2007-05-23 Christopher W. Mauche

The archetypical flare star UV Cet was observed by MeerKAT on 5-6 October 2021. A large radio outburst with a duration of $\sim\!2$ hr was observed between 886-1682 MHz with a time resolution of 8s and a frequency resolution of 0.84 MHz,…

Solar and Stellar Astrophysics · Physics 2022-08-31 Timothy Bastian , Bill Cotton , Gregg Hallinan

Radio activity has been observed in a large variety of stellar objects, including in the last few years, ultra-cool dwarfs. To explore the extent of long-term radio activity in ultra-cool dwarfs, we use data taken over an extended period of…

Astrophysics · Physics 2009-11-13 A. Antonova , J. G. Doyle , G. Hallinan , A. Golden , C. Koen

The nature of two recently discovered radio emitters with unusually long periods of 18min (GLEAM-X J1627-52) and 21min (GPM J1839-10) is highly debated. Their bright radio emission resembles that of radio magnetars, but their long…

Coherent radio bursts detected from M dwarfs have some analogy with solar radio bursts, but reach orders of magnitude higher luminosities. These events trace particle acceleration, powered by magnetic reconnection, shock fronts (such as…

Solar and Stellar Astrophysics · Physics 2019-02-13 Jackie Villadsen , Gregg Hallinan

AE Aqr was until recently the only known magnetic cataclysmic variable (MCV) containing a rapidly spinning (33.08 s) white dwarf (WD). Its radio emission is believed to be a superposition of synchrotron emitting plasmoids, because it has a…

Solar and Stellar Astrophysics · Physics 2022-01-19 Paul E. Barrett

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…

High Energy Astrophysical Phenomena · Physics 2023-03-03 Margaret E Ridder , Craig O Heinke , Gregory R Sivakoff , Andrew K Hughes

We detect radio emission in an additional two epochs of the ultracool dwarf binary LP 349- 25, finding that the observed emission is broadband and steady on timescales between 10s and 10.7 hours, as well as on timescales of 0.6 and 1.6…

Solar and Stellar Astrophysics · Physics 2009-07-24 R. A. Osten , N. Phan-Bao , S. L. Hawley , I. Neill Reid , R. Ojha

In cataclysmic variables (CVs), accretion onto white dwarfs produces high temperature, high density plasmas. They cool down from kT~10 keV via bremsstrahlung continuum and K and L shell line emissions. The small volume around white dwarfs…

Astrophysics · Physics 2007-05-23 Koji Mukai

DG CVn is an eruptive variable star and represents the closest member of the known sample of complex periodic variables, or scallop-shell stars. Over the years, this M dwarf binary system has shown significant flaring activity at a wide…

Recently, a number of ultracool dwarfs have been found to produce periodic radio bursts with high brightness temperature and polarization degree; the emission properties are similar to the auroral radio emissions of the magnetized planets…

Solar and Stellar Astrophysics · Physics 2015-06-03 A. A. Kuznetsov , J. G. Doyle , S. Yu , G. Hallinan , A. Antonova , A. Golden
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