TITLE: GCN CIRCULAR NUMBER: 7379 SUBJECT: GRB080307, optical upper limit DATE: 08/03/10 06:59:51 GMT FROM: Hiroki Tanaka at U of Miyazaki H. Tanaka, R. Hara, K.Kono, N.Ohmori, H.hayasi, M.Yamauchi, E.Sonoda (University of Miyazaki) We have observed the field covering the error circle of GRB080307 (GCN 7366, M.R. Goad et al.) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started 11:25:17 UT, but it was cloudy then,so we got first image at 13:44:43 UT, ~141 min 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 (GCN 7369, N. R. Tanvir) the upper limits are as follows: -------------------------------------------------------------- Start(UT) End(UT) Num. of frames Limit (mag.) -------------------------------------------------------------- 14:01:59 14:02:29 1 ~16.36 14:01:59 17:26:12 20 ~16.99 ---------------------------------------------------------------