[vsnet-grb-info 8593] GRB091024 optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  10101
SUBJECT: GRB091024 optical observations
DATE:    09/10/29 08:33:52 GMT
FROM:    Vladimir Sokolov at SAO RAS  <sokolov at sao.ru>

A. Moskvitin, T. Fatkhullin (SAO-RAS Niznijh Arkhyz, Russia),
on behalf of a larger colaboration, report:

We observed the field of the GRB 091024 afterglow (Marshall et al., GCN
10062) with the Zeiss-1000 telescope of SAO RAS, Russia. The observations
were carried out starting from October, 24.651 (15:37 UT) till October,
24.976 (23:26 UT). In total 29 * 300 sec. exposures in the Rc-band and
29 * 300 sec. exposures in the V-band were obtained. During the observations
we detected a faint fading object at the position reported by Mundell et al.
(GCN 10063) as well as a small extended object with R~20.8 in ~2 arcseconds
to the North-West from the afterglow (see also Kann and Laux GCN 10077).
The brightness of the OT in the first stacked R-band images (the mean epoch
is 16:52 UT) is R = 20.7 +/- 0.2 (we admit some contribution in flux from
the extended object). It is not clear at this stage if the extended object
is a host galaxy or a foreground galaxy responsible for the absorption line
system reported by Cucchiara et al. (GCN 10065) and Cenko et al.
(GCN 10093). The data analysis is in progress. Photometry was carried out
using nearby USNO B1.0 stars (R2 magnitudes).

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