GCN Circular 12863
Subject
GRB 120119A: GROND Detection of the Optical/NIR Afterglow
Event
Date
2012-01-19T05:27:34Z (14 years ago)
From
Patricia Schady at MPE/Swift <pschady@mpe.mpg.de>
P. Schady, V. Sudilovsky, J. Greiner (all MPE Garching) and T.Kruehler
(DARK/NBI) report on behalf of the GROND team:
We observed the field of GRB 120119A (Swift trigger 512035; Beardmore
et al., GCN #12859) 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 04:08 UT, 3.5 min after the GRB trigger, and
are continuing. They were performed at an average seeing of 0.9" and
at an average airmass of 1.0.
We found a single point source consistent with the UVOT afterglow
position.
Based on the first 2.4 min of total exposures in g'r'i'z' and 4 min in
JHK, we estimate preliminary magnitudes (all in AB) of
g' = 18.8 +- 0.1 mag,
r' = 17.7 +- 0.1 mag,
i' = 16.8 +- 0.1 mag,
z' = 16.2 +- 0.1 mag,
J = 15.2 +- 0.1 mag,
H = 14.6 +- 0.1 mag and
K = 14.0 +- 0.1mag
Given magnitudes are calibrated against SDSS zeropoints as well as
2MASS field stars and are not corrected for the expected Galactic
foreground extinction corresponding to a reddening of E_(B-V)=0.11 mag
in the direction of the burst (Schlegel et al. 1998).