TITLE:   GCN CIRCULAR
NUMBER:  21740
SUBJECT: LIGO/Virgo G298048: Further ATCA follow-up of SSS17a in NGC 4993
DATE:    17/08/29 03:49:22 GMT
FROM:    Tara Murphy at U of Sydney  <tara.murphy@sydney.edu.au>

C. Lynch (University of Sydney), T. Murphy (University of Sydney),
D. Kaplan (UWM), K. Bannister (CSIRO), D. Dobie (University of Sydney)
on behalf of the VAST collaboration.

Following Lynch et al. (LVC GCN 21670), we observed a third epoch of
NGC 4993 with the Australia Telescope Compact Array at 8.5 and 10.5 GHz.
Observations started at 2017-08-27 23:26:24.9 UT and ended at
2017-08-28 9:00:00 UT with approximately 2.3 hours of on-source time.

We fit and subtracted a point-source at the optical position of NGC 4993
(13:09:47.71, -23:23:01.79; Skrutskie et al. 2003, 2MASS Extended Source
Catalog). From this we set a 3-sigma upper limit of 54 uJy and 39 uJy on
radio emission from SSS17a at 8.5 and 10.5 GHz respectively.

Subsequent epochs are planned.

Thank you to CSIRO staff for supporting these observations.