GCN Circular 6951
Subject
GRB 071020: ROTSE-III Analysis of Optical Counterpart
Date
2007-10-20T08:07:20Z (17 years ago)
From
Fang Yuan at ROTSE <yuanfang@umich.edu>
F. Yuan (U Mich), E.S. Rykoff (UCSB), T.A. McKay (U Mich), B. E.
Schaefer (Louisiana State), R. Quimby (Caltech), H. Swan (U Mich),
report on behalf of the ROTSE collaboration:
ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB
071020 (Swift trigger 294835; Holland, et al., GCN6949) and detected the
optical counterpart (Schaefer, et al., GCN 6948). During our first 80
seconds observation (starting 25.6 sec after the burst), the OT faded
with a decay index of 1.52 +/- 0.03.
We notice that the burst location is 9.7h^-1 kpc from the central bulge
of SDSS J075843.38+325141.7, a galaxy with an old stellar population
located at z=0.0166. DR6 SDSS data suggest this galaxy as M_r ~ -19.4,
and a central velocity dispersion of 135 km/s.