TITLE: GCN CIRCULAR NUMBER: 7691 SUBJECT: GRB080503, RIMOTS optical upper limit DATE: 08/05/07 07:44:10 GMT FROM: Hiroki Tanaka at U of Miyazaki H. Tanaka, N. Ohmori, H. Hayasi, R. Hara, K. Kono, M. Yamauchi (University of Miyazaki) We have observed the field covering the error circle of GRB080503 (GCN 7669, M.R. Goad et al.) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started 15:25:55 UT; about 180 minutes after the Swift trigger time. We have compared our data of 30 sec exposures with the USNO-A2.0 catalog,there is no new source at the reported position the upper limits are as follows: -------------------------------------------------------------- Start(UT) End(UT) Num. of frames Limit (mag.) -------------------------------------------------------------- 15:26:57 15:27:27 1 ~16.82 15:26:57 16:24:33 57 ~17.43 ---------------------------------------------------------------