TITLE:   GCN CIRCULAR
NUMBER:  7869
SUBJECT: GRB 080603b: optical observation
DATE:    08/06/11 23:29:52 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

V. Rumyantsev (CrAO),  A. Pozanenko (IKI) report on behalf of larger GRB
follow-up collaboration:

We observed the field of  Swift GRB 080603b (Mangano et al., GCN 7794)  on
June 06 betwen (UT) 19:20:31 - 20:27:07  with Zeiss-1000 (Simeiz) telescope
of  CrAO observatory with favorable weather conditions. We do not detect
optical afterglow (Rujopakarn, et al., GCN 7792) in a combined image  of
R-band up to 22.5 (3sigma). A photmetry is obtained in comparison with
nearby USNOB-1.0 stars:

UT,       Exposure,   UL
(mid time)

3.011 d   33x120 s    22.5 (3sigma)

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