[vsnet-grb-info 11004] GRB 111005A: ATCA radio upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  12421
SUBJECT: GRB 111005A: ATCA radio upper limit
DATE:    11/10/07 12:15:26 GMT
FROM:    Dong Xu at Weizmann Inst  <dong.dark at 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.