| 23rd of August 2018 |
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| An ASKAP pilot survey for variable and transient sources |
| by Shivani Bhandari |
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Bhandari et al. have conduced a pilot survey for variable and
transient sources at 1.4 GHz on the timescale of days with the
Australian Square Kilometre Array Pathfinder (ASKAP). The search
yielded nine potential variable sources which are identified to be
compact active galactic nucleus undergoing refractive interstellar
scintillation. We also detect a highly variable source with flux
density variations greater than 50% over a time interval of a decade
between the Sydney University Molonglo Sky Survey (SUMSS) and our
latest ASKAP observations. We find this source to be consistent with
the properties of long-term variability of a quasar. No transients
were detected on time-scales of days and we place an upper limit in
the above plot (blue point). The future VAST-Wide survey with
36-ASKAP dishes will probe the transient phase space with similar
cadence to our pilot survey, but better sensitivity, and will detect
and monitor rarer brighter events.
More details are given in the full paper , which is published in Monthly Notices of the Royal Astronomical Society.
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