GCN Circular 11421
Subject
GRB 101117B: GROND Upper limits
Date
2010-11-22T19:05:49Z (14 years ago)
From
Jonny Elliott at MPE/GROND <jonnyelliott@mpe.mpg.de>
J. Elliott, R. Filgas, J. Greiner, P. Schady and T. Kruehler (all MPE
Garching) report
on behalf of the GROND team:
We observed the field of GRB 101117B (Swift trigger 438675; Wolf et al.,
GCN #11411) 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 at La Silla
Observatory (Chile).
Observations started at 05:15 UT on November 19, 34 hours after the GRB
trigger, and have total exposure of 6003 s in g'r'i'z' and 4800 s in JHK.
They were performed at an average seeing of 2.0" and at an average airmass
of 1.8.
We do not detect a source within the UVOT error circle reported by Holland
& Wolf (GCN #11420) down to the following 3 sigma upper limits (all in
AB):
g' > 23.7
r' > 23.8
i' > 23.5
z' > 23.3
J > 21.7,
H > 21.2 and
K > 20.4
The given limits are derived based on calibrating the images against GROND
zeropoints and 2MASS field stars and are not corrected for the Galactic
foreground extinction corresponding to a reddening of E_(B-V)= 0.38 in the
direction of the burst (Schlegel et al. 1998).