GCN Circular 12605
Subject
GRB 111129A, GROND afterglow observations
Event
Date
2011-11-30T09:34:58Z (15 years ago)
From
Andrea Rossi at TLS Tautenburg <rossi@tls-tautenburg.de>
A. Rossi, A. Nicuesa Guelbenzu (all Tautenburg)
and J. Greiner (MPE) report on behalf of the GROND team:
We observed the field of GRB 111129A (Racusin, GCN 12600)
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 00:30 UT on November 30, about 8.2 hr after the
burst,
and continued for about 2 hrs. They were performed at an average seeing of 1
arcsec and an average airmass of 1.8.
We detect the afterglow discovered by Racusin et al. (GCN 12600) in the
optical/NIR. At a mean time of November 30, 01:31 UT
(9.25 hours after the trigger)
with exporures times of 24.3 minutes in griz and 20 min in JHK,
we measure the following preliminary magnitudes (AB system):
g' = 22.9 +/- 0.1,
r' = 22.3 +/- 0.1,
i' = 21.8 +/- 0.1,
z = 21.3 +/- 0.1,
J = 20.5 +/- 0.2,
H = 19.8 +/- 0.2,
K = 19.1 +/- 0.3
Optical data are calibrated against GROND zeropoints and
NIR against 2MASS field stars.