GCN Circular 21395
Subject
GRB 170728B: VLA radio afterglow detection
Date
2017-07-31T04:27:16Z (7 years ago)
From
Wen-fai Fong at U of Arizona <wfong@email.arizona.edu>
W. Fong (University of Arizona), T. Laskar (NRAO/UC Berkeley), K. D.
Alexander (Harvard) and E. Berger (Harvard) report:
"We observed the position of GRB 170728B (Cenko et al., GCN 21371; Yassine
et al., GCN 21380; Stanbro & Meegan, GCN 21383) with the Karl G. Jansky
Very Large Array (VLA) beginning on 2017 Jul 29.075 UT (2.75 hr post-burst)
at a mean frequency of 6 GHz. We obtained a second set of observations
beginning on 2017 Jul 29.811 UT (20.4 hr post-burst) at mean frequencies of
6 and 10 GHz.
We do not detect any radio counterpart in our first set of observations at
2.75 hr, while we clearly detect a radio source in our second set of
observations at both frequencies at 20.4 hr at the position:
RA(J2000) = 15:51:55.45
Dec(J2000) = +70:07:21.2
with an uncertainty of 0.2" in each coordinate. This position is coincident
with the reported optical source (D'Avanzo et al., GCN 21372