TITLE: GCN CIRCULAR NUMBER: 6184 SUBJECT: GRB 070306, optical observation DATE: 07/03/09 16:31:09 GMT FROM: Shouta Maeno at U.of Miyazaki S.Maeno, E.Sonoda, R.Hara, H.Tanaka, K.Tanaka, T.Matsumura, M.Yamauchi (University of Miyazaki) We have observed the field covering the error region of GRB 070306 (GCN 6169) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started from 16:43:36 UT on Mar. 6 (128 s after the trigger). We have compared our data of 30 sec exposures with the USNO-A2.0 catalog. There is no new source at the XRT position(GCN 6172). The upper limit is as follows: -------------------------------------------------------------- Start(UT) End(UT) Num. of frames Limit (mag.) -------------------------------------------------------------- 16:43:36 16:44:06 1 ~15.8 16:45:24 16:59:40 9 ~17.0 ---------------------------------------------------------------