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 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.