A T N F    D a i l y    A s t r o n o m y    P i c t u r e

29th of April 2024
ASKAP images, in total intensity and circular polarisation, of two stars and a pulsar.
Multi-epoch sampling of the radio star population with ASKAP
by Pritchard et al.
The population of radio-loud stars has to date been studied primarily through either targeted observations of a small number of highly active stars or widefield, single-epoch surveys that cannot easily distinguish stellar emission from background extra-Galactic sources. As a result it has been difficult to constrain population statistics such as the surface density and fraction of the population producing radio emission in a particular variable or spectral class. Pritchard et al. present a sample of 36 radio stars detected in a circular polarisation search of the multi-epoch Variables and Slow Transients (VAST) pilot survey with ASKAP at 887.5 MHz. Through repeat sampling of the VAST pilot survey footprint they find an upper limit to the duty cycle of M-dwarf radio bursts of 8.5 per cent, and that at least 10±3 per cent of the population should produce detectable radio bursts. Based on these rates, the authors anticipate that around 200 ± 50 new radio star detections will be made per year over the full VAST survey.

The figure above shows Stokes I (top panels) and V (bottom panels) cutouts of two identified stars (panels d and e) and a pulsar (panel f). The restoring beam is shown as the ellipse in the lower left of each panel, and green and black dotted ellipses trace the shape of the selavy source-finder components.

<<   |   archive   |   about   |   today   *   ATNF   |   Parkes   |   ATCA   |   Mopra   |   VLBI   |   ASKAP   |   >>