TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2752
SUBJECT: GRB040924, RTT150 optical observation
DATE:    04/09/26 21:01:40 GMT
FROM:    Irek Khamitov at TUG  <irekk@tug.tug.tubitak.gov.tr>

I. Khamitov, Z. Aslan (TUG), C. Yesilyaprak (Akdeniz Univ.),
U. Kiziloglu (METU), E.Gogus, A. Alpar (Sabanci Univ.),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
I. Bikmaev, N. Sakhibullin (KSU)

report:

  We observed the afterglow of GRB 040924 (Fenimore et al. GCN 2735, Fox 
and Moon, GCN 2734) with Russian-Turkish 1.5-m telescope (Bakyrlytepe, 
TUBITAK National Observatory, Turkey). We made 33x300s images in R between 
Sep. 25, 23:45 UT, and Sep. 26, 2:45 UT. The observations were hampered by 
the bright-moon and bad seeing (1.7 arcsec). The object was clearly 
detected near the limit of the combined image. We estimate its magnitude 
to be m_R=23.7+/-0.2.

This magnitude is consistent with power law decay with index -1.16, 
obtained in our previous observations (GCN 2749). The KAIT earlier 
measurements (GCN 2748) seem to be consistent with this power law as well. 
Therefore, to the first approximation, the whole light curve of the GRB 
040924 afterglow can be described as a single power law with index -1.16.

The combined light curve can be found at:

http://hea.iki.rssi.ru/~rodion/040924/lc_all.jpg
or
http://www.tug.tubitak.gov.tr/~irekk/grb/grb040924/lc_all.jpeg

The finding charts:

http://hea.iki.rssi.ru/~rodion/040924/fcharts.html
or
http://www.tug.tubitak.gov.tr/~irekk/grb/grb040924/fcharts.html

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