GCN Circular 12421
Subject
GRB 111005A: ATCA radio upper limit
Date
2011-10-07T12:15:26Z (13 years ago)
From
Dong Xu at Weizmann Inst <dong.dark@gmail.com>
D. Xu (WIS), M. Michalowski (U. Edinburgh), J. Stevens, P. Edwards, D.
Bock, B. Hiscock, R. Wark (CSIRO) report on behalf of a larger
collaboration:
We observed the BAT field of GRB 111005A (Saxton et al., GCN 12413)
with the Australia Telescope Compact Array (ATCA), starting at 05:13
UT, 7th Oct. 2011 (i.e., 45.1 hours after the burst) at frequencies of
5.5/9 GHz.
The source of NVSS 145310-194331, or EVLA-S2 by Zauderer et al. (GCN
12419), in the field was clearly detected in our 5.5GHz image. But no
radio source was detected near or in the local galaxy, ESO 580-49 at
z=0.013 (Levan et al., GCN 12414), to a 3sigma upper limit of ~114
microJy at 5.5GHz.
Comparison with the earlier detection of a radio transient, EVLA-S1,
in the galaxy (GCN 12419; and typical EVLA 3sigma upper limit of
~60-100 microJy from previous GRB events) reveals that probably this
radio transient has been decaying over the past ~2 days.
Further ATCA observations of the field are underway.