TITLE:   GCN CIRCULAR
NUMBER:  9727
SUBJECT: GRB 090728, RIMOTS optical upper limits
DATE:    09/07/28 17:32:46 GMT
FROM:    Hidenori Hayasi at Miyazaki U  <hayasi@astro.miyazaki-u.ac.jp>

Sub:GRB 090728, RIMOTS optical upper limits  

K.Noda, H.Hayasi, E.Sonoda, N.Ohmori, K.Kono  
A.Daikyuji, Y.Nisioka, M.Yamauchi
(University of Miyazaki)

 We have observed the field covering the error circle of
GRB 090728 (Swift trigger 358574, GCN 9725, V. Mangano et al.) 
with the unfiltered CCD camera on the 30-cm telescope 
at University of Miyazaki.
The observation was started 14:46:53 UT, about 23 sec
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. 
(Swift trigger 358574, GCN 9725, V. Mangano et al.) 

the upper limits are as follows:
--------------------------------------------------------------
Start(UT)   End(UT)    Num. of frames    Limit (mag.)
--------------------------------------------------------------
14:59:59	15:00:29          1            13.8
14:46:53	15:00:29         11            15.4
---------------------------------------------------------------