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GCN Circular 4612

GRB050121b: optical observation
2006-01-28T02:17:21Z (18 years ago)
Alexei Pozanenko at IKI, Moscow <>
D. Sharapov (MAO, and NOT La Palma),  M. Ibrahimov (MAO), A. Pozanenko
(IKI), V. Rumyantsev (CrAO) on behalf of larger GRB follow up collaboration

We observed  error box of  GRB051221b (Boyd et al., GCN 4376) with 1.5m
telescope of Maidanak Astronomical Observatory on Dec. 22 between (UT) 15:41
and 16:06. A set of 7x180 s images were obtained in R-band. We do not detect
the object at the location of the candidate optical counterpart reported by
Halpern & Tyagi (GCN 4381). Limiting magnitude of the stacked image is based
on USNO-B1.0:

Obs. time,           Exposure,  mag.(UL),Seeing
(UT)                 (s)

Dec.22 15:41 - 16:06 1260       22.3     1.2"

Combined images can be found at

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