[vsnet-grb-info 2585] GRB051211B: optical observations

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4422
SUBJECT: GRB051211B: optical observations
DATE:    06/01/02 12:34:50 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

D. Sharapov (MAO, and NOT La Palma), N.Marshalkina, M. Ibrahimov (MAO),
A.Pozanenko (IKI), V.Rumyantsev (CrAO) on behalf of larger GRB follow up
collaboration report:

We observed refined error box of  X-ray afterglow detected by Swift/XRT (La
Parola et al. GCN 4338) of GRB051211B (Mereghetti et al. GCN 4327) with 1.5m
telescope of Maidanak Astronomical Observatory on Dec. 12 and Dec.17. Sets
of R images of 10x180 s were accumulated in both epochs. We do not detect
the candidate in afterglow at coordinates RA(J2000) =23:02:41.57, Dec(J2000)
=+55:04:51.5 mentioned by  M. Jelinek et al. in GCN 4358. Object to the
North-West from fading object referred in GCN 4358 as a possible host galaxy
is well detected in our combined images in the both epochs. Using USNO-B1.0
catalog we estimate upper limit and possible host galaxy brightness as
following:

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

Dec.12 17:16-17:56  1800  21.077+/-0.075  22.0   1.2"
Dec.17 14:09-14:45  1800  21.167+/-0.060  22.3   1.1"

The source mentioned by Khamitov et al in GCN 4336 is marginally detected on
our combined image on Dec.12, and is unlikely to be an afterglow.  We would
note that the candidate in afterglow at coordinates RA(J2000) =23:02:41.57,
Dec(J2000) =+55:04:51.5 is well visible in RTT150 image.

Combined images can be found at http://grb.rssi.ru/GRB051211b/.