A circular polarisation survey for radio stars with the Australian SKA Pathfinder

Abstract

We present results from a circular polarisation survey for radio stars in the Rapid ASKAP Continuum Survey (RACS). RACS is a survey of the entire sky south of $\delta =+41^{\circ }$ being conducted with the Australian Square Kilometre Array Pathfinder telescope (ASKAP) over a 288 MHz wide band centred on 887.5 MHz. The data we analyse includes Stokes I and V polarisation products to an RMS sensitivity of 250 $\mu$Jy PSF${}^{-1}$. We searched RACS for sources with fractional circular polarisation above 6 per cent, and after excluding imaging artefacts, polarisation leakage, and known pulsars we identified radio emission coincident with 33 known stars. These range from M-dwarfs through to magnetic, chemically peculiar A- and B-type stars. Some of these are well known radio stars such as YZ CMi and CU Vir, but 23 have no previous radio detections. We report the flux density and derived brightness temperature of these detections and discuss the nature of the radio emission. We also discuss the implications of our results for the population statistics of radio stars in the context of future ASKAP and Square Kilometre Array surveys.

18 pages, 10 figures, to be published in MNRAS

References in corpus (26)

• Array Programming with NumPy
• The NumPy array: a structure for efficient numerical computation
• The LOFAR Two-metre Sky Survey - I. Survey Description and Preliminary Data Release
• GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey I: A low-frequency extragalactic catalogue
• Second ROSAT all-sky survey (2RXS) source catalogue
• Science with ASKAP - the Australian Square Kilometre Array Pathfinder
• The H$\alpha$ emission of nearby M dwarfs and its relation to stellar rotation
• The Rapid ASKAP Continuum Survey I: Design and First Results
• The Molonglo Galactic Plane Survey (MGPS-2): Compact Source Catalogue
• SkyMapper Southern Survey: Second Data Release (DR2)
• Evolutionary state of magnetic chemically peculiar stars
• Fluxes in Hαand Ca II H and K for a sample of Southern stars
• A White Light Megaflare on the dM4.5e Star YZ CMi
• The Australian Square Kilometre Array Pathfinder: System Architecture and Specifications of the Boolardy Engineering Test Array
• The Australian Square Kilometre Array Pathfinder: Performance of the Boolardy Engineering Test Array
• Stellar magnetosphere reconstruction from radio data. Multi-frequency VLA observations and 3D-simulations of CU Virginis
• ASKAP Detection of Periodic and Elliptically Polarized Radio Pulses from UV Ceti
• Do A-type stars flare?
• Tentative Evidence for Relativistic Electrons Generated by the Jet of the Young Sun-like Star DG Tau
• The Near-Ultraviolet Luminosity Function of Young, Early M-Type Dwarf Stars
• HAZMAT II: Ultraviolet Variability of Low-Mass Stars in the GALEX Archive
• The magnetic field and spectral variability of the He-weak star HR 2949
• A Sample of Candidate Radio Stars in FIRST and SDSS
• The Coherent Radio Emission from the RS CVn Binary HR 1099
• A sub-AU outwardly truncated accretion disk around a classical T Tauri star
• Differences in radio emission from similar M dwarfs in the binary system Ross 867-8

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• V-LoTSS: The Circularly-Polarised LOFAR Two-metre Sky Survey
• Discovery of ASKAP J173608.2-321635 as a Highly-Polarized Transient Point Source with the Australian SKA Pathfinder
• Periodic Radio Emission from the T8 Dwarf WISE J062309.94-045624.6
• Searching for pulsars associated with polarised point sources using LOFAR: Initial discoveries from the TULIPP project
• Serendipitous discovery of radio flaring behaviour from a nearby M dwarf with MeerKAT
• The TESS View of LOFAR Radio-Emitting Stars
• Discovery of PSR J0523-7125 as a Circularly Polarized Variable Radio Source in the Large Magellanic Cloud
• The detection of radio emission from known X-ray flaring star EXO 040830-7134.7
• Testing a scaling relation between coherent radio emission and physical parameters of hot magnetic stars
• The Mouse that Squeaked: A small flare from Proxima Cen observed in the millimeter, optical, and soft X-ray with Chandra and ALMA
• A pilot ASKAP survey for radio transients towards the Galactic Centre
• Radio Afterglows from Compact Binary Coalescences: Prospects for Next-Generation Telescopes
• Radio Variable and Transient Sources on Minute Timescales in the ASKAP Pilot Surveys
• A search for thermal gyro-synchrotron emission from hot stellar coronae
• Searching for stellar flares from low mass stars using ASKAP and TESS
• Time-lapse Very Long Baseline Interferometry Imaging of the Close Active Binary HR 1099
• Radio Transients and Variables in the Tenth Deeper, Wider, Faster Observing Run
• Detection of coherent low-frequency radio bursts from weak-line TTauri stars
• The Potential of Detecting Radio-flaring Ultracool Dwarfs at L band in the FAST Drift-scan Survey
• Finding radio transients with anomaly detection and active learning based on volunteer classifications
• Periodic Radio and X-ray Emission from an Accreting White Dwarf Binary
• The stellar population in the SARAO MeerKAT Galactic Plane Survey
• System equivalent flux density of Stokes I, Q, U, V of a polarimetric interferometer
• Spectral features and variable circular polarisation in the radio emission from the pre-cataclysmic variable QS Vir
• Structural and spectral properties of Galactic plane variable radio sources
• Orbital motion and dynamical mass of the complex periodic variable binary system 2MASS J05082729-2101444
• Discovery of eight 'Main-sequence Radio Pulse emitters' using the GMRT: clues to the onset of coherent radio emission in hot magnetic stars