[vsnet-grb-info 5137] GRB 071003: P60 Confirmation of Optical Afterglow

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6839
SUBJECT: GRB 071003: P60 Confirmation of Optical Afterglow
DATE:    07/10/03 10:58:39 GMT
FROM:    S. Bradley Cenko at Caltech  <cenko at srl.caltech.edu>

S. B. Cenko (Caltech) and D. B. Fox (Penn State) report on behalf of a
larger collaboration:

We have imaged the field of GRB071003 (Schady et al., GCN 6837) with the
automated Palomar 60-inch telescope.  Observations began approximately 3
minutes after the burst (~ 07:44 UT 10 October) and were taken at high
airmass (~ 2.5).  At the location of the optical afterglow candidate (Li,
GCN 6838) we detect a fading source in the g, R, i', and z' filters.
While photometry is complicated by the nearby bright star (Li, GCN 6838),
we estimate a magnitude of R ~ 14.5 in our first 60 s image (photometric
calibration was performed relative to several nearby objects from the
USNO-B catalog).  The corresponding decay index is ~ -1.0.