[vsnet-grb-info 5724] GRB080307, optical upper limit

[GCN Circulars]

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  <hiro0218 at astro.miyazaki-u.ac.jp>

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
---------------------------------------------------------------