[vsnet-grb-info 11049] GRB 111020A: Gemini-South i-band observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  12467
SUBJECT: GRB 111020A: Gemini-South i-band observations
DATE:    11/10/21 01:58:38 GMT
FROM:    Wen-fai Fong at CFA  <wfong at cfa.harvard.edu>

W. Fong (Harvard), E. Berger (Harvard) and D. Fox (PSU) report:

We imaged the location of the short GRB 111020A (GCN 12460) with GMOS on the
Gemini-South 8-m telescope on 2011 October 21.01 UT (mid-time of 17.7 hours
post-burst).  We obtained 9x180s exposures in i-band with 0.8" seeing.

We find no sources within the enhanced XRT error circle (GCN 12463) to a
3-sigma limiting magnitude of i~25 mag.

However, we find two faint objects just outside of the XRT error circle with
coordinates (J2000):

S1:
RA = 19:08:12.501
Dec = -38:00:41.80

S2:
RA = 19:08:12.698
Dec = -38:00:44.46

S1 has a brightness of i~23.7 mag and appears to be point-like. S2 is
fainter, at the threshold of detectability with a brightness of i~25 mag.

The nearest galaxy is located at:

G1:
RA = 19:08:12.231
Dec = -38:00:48.80

with a magnitude of i~23.3 mag, and 6.2" from the center of the XRT error
circle.