GCN Circular 12595
Subject
GRB 111123A, GROND observations
Date
2011-11-24T16:04:07Z (12 years ago)
From
Ana Nicuesa at TLS Tautenburg <ana@tls-tautenburg.de>
A. Rossi, A. Nicuesa Guelbenzu, S. Klose (all Tautenburg), P. Afonso
(American River College), and J. Greiner (MPE) report on behalf of the
GROND team:
We observed the field of GRB 111123A (Stamatikos, GCN 12587)
simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP
120, 405) mounted at the 2.2-m MPI/ESO telescope on La Silla. Observations
started at 6:30 UT on November 24, about 12 hr after the burst, and
continued for about 1.5 hr. They were performed at an average seeing of 1
arcsec and an average airmass of 1.5.
We do not detect the source discovered by Xu et al. (GCN 12589; see
also Fugazza et al. GCN 12593). At a mean time of November 24, 7:10 UT,
we measure the following preliminary upper limits (AB magnitudes):
g' > 24.5,
r' > 24.6,
i' > 23.7,
J > 21.2,
H > 20.9,
K > 19.9.
The data are calibrated against GROND zeropoints and 2MASS field stars.