GCN Circular 7283
Subject
GRB 080210: GOND detection in all bands and redshift upper limit
Event
Date
2008-02-10T10:06:35Z (18 years ago)
From
Jochen Greiner at MPI <jcg@mpe.mpg.de>
A. Kuepcue Yoldas, A. Yoldas, J. Greiner (all MPE Garching),
S. Klose (Tautenburg Obs), report for the GROND team:
We observed the field of GRB 080210 detected by Swift/BAT (Grupe et al.
2008, GCN 7281) simultaneously in grizJHK with GROND (Greiner et al. 2008,
astro-ph/0801.4801), mounted at the 2.2m MPI/ESO telescope at La Silla (Chile).
Observations started on Feb. 10, at 09:00 UT (1 hr after the GRB),
when the GRB location was becoming visible at 20 degrees above horizon.
We detect the optical afterglow reported by Klotz et al. (2008, GCN 7280)
and Grupe et al. (2008, GCN 7281) in all filters. At 9:02 UT we measure
g'=20.97, r'=19.9, i'=19.61, z'=19.52, J=17.2, H=16.4 and K=15.6, with
errors of +-0.04 in the g'r'i'z' bands, and 0.13 in JHK. The g'-r' color
is consistent with the Ly-break being below the g'-band. Thus, the
redshift is smaller than 3.5, despite the possible expectation from the
long T90 duration of the GRB (and being an image trigger).
The afterglow has clearly faded since the TAROT and UVOT measurements, and
also continues to fade since the start of our observations.