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Wang et al. present the results of a radio transient and polarisation
survey towards the Galactic Centre, conducted as part of the ASKAP
Variables and Slow Transients (VAST) pilot survey. The survey region
consisted of five fields, all within 10 degrees of the Galactic
Plane. Each field was observed for 12 minutes, with between 7 and 9
repeats on cadences of between one day and four months. Eight highly
variable sources and seven highly circularly-polarised sources (14
unique sources in total) were detected. Seven of these sources are
known pulsars including the rotating radio transient PSR J1739–2521
and the eclipsing pulsar PSR J1723–2837. One of them is a low mass
X-ray binary, 4U 1758–25. Three of them are coincident with optical or
infrared sources and are likely to be stars. The remaining three may
be related to the class of Galactic Centre Radio Transients (including
a highly likely one, VAST J173608.2–321634, that has been reported
previously), although this class is not yet understood. In the coming
years, ~40 bursts from this kind of source can be expected to be
detected with the proposed four-year VAST survey if the distribution
of the source is isotropic over the Galactic fields.
The image above is a mosaicked image of the RACS-low Low Galactic
Latitude region. The white dashed line shows the boundary of VAST Low
Galactic Latitude region. A grid of Galactic coordinates is shown in
grey dashed lines. The transient and circularly polarised (Stokes V)
sources found are shown as orange circles and magenta hollow circles,
respectively.
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