TITLE:   GCN CIRCULAR
NUMBER:  3198
SUBJECT: GRB 050408: First Optical observations with TFOSC at the RTT150
DATE:    05/04/09 02:08:11 GMT
FROM:    Irek Khamitov at TUG  <irekk@tug.tug.tubitak.gov.tr>

Z. Aslan,I. Khamitov,T. Ozisik, K. Uluc(TUG), U. Kiziloglu (METU),I. 
Bikmaev, R. Gumerov, N. Sakhibullin (KSU/AST), A. Alpar (SabUni), R. 
Burenin, M. Pavlinsky, R. Sunyaev (IKI),
report:

    We have observed the error box of GRB 050408(GCN 3189 and  GCN 3191) 
with TFOSC (the imaging and spectroscopic camera of the TUBITAK National 
Observatory, Turkey) attached to the Russian-Turkish 1.5-m telescope 
(Bakyrlytepe, Turkey). We made series of 30s and 60s  exposures in Rc, 
starting at 18:46 UT. We have found the OT candidate indicated in GCN 3193 
getting fainter with a spectral index of -0.63. We have determined its 
postion and magnitudes using USNO-B1. The position and the preliminary R 
photometry are as follows:

RA: 12:02:17.31  Dec: +10:51:9.4 (+/- 0.1 arcsec)(2000)

T-T0(hours)        Rc
3.7            20.94 +/- 0.1
4.4            21.05
5.4            21.17
6.7            21.31
8.3            21.50

The reductions are in progress.
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