TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3511 SUBJECT: GRB 050603: Afterglow Identification from LCO DATE: 05/06/03 11:01:08 GMT FROM: Edo Berger at Carnegie Obs Edo Berger and Andy McWilliam (Carnegie Observatories) report: "On 2005, June 3.412 UT (3.4 hrs after the burst) we imaged the BAT error circle of GRB 050603 (GCN 3509) with the du Pont 100-inch telescope at Las Campanas Observatory in the R-band. Within the 4' radius error circle we find a single bright source (R~16.5 mag) which is not present in the DSS at coordinates (J2000): RA = 02:39:57 DEC=-25:10:54 with an uncertainty of about 0.5" in each coordinate. At the present we do have information about variability."