TITLE:   GCN CIRCULAR
NUMBER:  2775
SUBJECT: GRB041006, optical observation
DATE:    04/10/07 00:17:13 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

B. Kahharov,  I. Asfandiyarov,  M. Ibrahimov,   D. Sharapov (UBAI),
A.Pozanenko (IKI),
V.Rumyantsev (CrAO),  G.Beskin (SAO) report:

We have observed the filed of error box of  GRB041006 (HETE #3570, M.
Galassi, et al. GCN 2770) starting Oct.6 15:49 (UT) with  1.5m telescope of
Mt.Maidanak High-altitude Observatory. Several BVRI images were taken
between 15:49 and 16:51. We confirm a fading source found by G. Da Costa et
al. (GCN 2765). Preliminary reduction of the data against the USNO-A2.0
catalog yield the following OT magnitudes in R

UT      exposure mag   err
15:49   180 s    18.7 (0.09)
16:46   300 s    19.1 (0.10)

The magnitudes assume a temporal decay index about 1.5 which is stepper than
found by P.A. Price, et al. (GCN 2771) and may indicate a brake of a light
curve of the OT.

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