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GCN Circular 12467

GRB 111020A: Gemini-South i-band observations
2011-10-21T01:58:38Z (13 years ago)
Wen-fai Fong at CFA <>
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):

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

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:

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
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