GCN Circular 5632
Subject
GRB 060926: MASTER: first minutes decay
Date
2006-09-27T15:54:15Z (18 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy,
A.Krylov, G.Borisov, A.Sankovich, V.Vladimirov, P.Gritsyk
Sternberg Astronomical Institute, Moscow Union 'Optic'
MASTER robotic system (http://observ.pereplet.ru)
responded to GRB060926 (Holland et al., GCN Circ 5612) under the good
conditions.
The first image was started at 2006-09-26 16:49:57 UT, 76 s after the GRB
time (355 mm telescope, 6 square degrees FOV, 2.1'' per pix, CCD Alta U16).
The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B).
We find faint OT on the first and on the coadded images at
position:
aplha = 17 35 43.66
dec = 13 02 18.3
err = +- 0.7''
wich coincided with the Holland et al.(GCN Circ 5612) OT position.
Our results:
T-T_grb mean time exp_time m (close to R) S/N
76 s - 106 s 91 s 30 s 17.5+-0.3 4.5
76 s - 360 s 218 s 5x30 s 18.2+-0.3 4
76 s - 820 s 448 s 10x30 s 18.3+-0.3 4
76 s - 1411 s 743 s 15x30 s 18.7+-0.3 4
1024 s - 1810 s 1417 s 10x30 s >19.7
We fitted these values with a powerlaw with a decay index of 0.69 up to 743 s.
This is steeper then the powerlaw OPTIMA-Burst
observations (GCN 5623, A. Stefanescu et al.).
The light curve is available at
http://observ.pereplet.ru/images/GRB060926/lc.jpg .
JPG-Images are available.
Small part with OT:
First - http://observ.pereplet.ru/images/GRB060926/GRB060926_1.jpg
Sum of 5 - http://observ.pereplet.ru/images/GRB060926/GRB060926_5.jpg
Sum of 10 - http://observ.pereplet.ru/images/GRB060926/GRB060926_10.jpg
The 2005 MASTER Survey Image
http://observ.pereplet.ru/images/GRB060926/GRB060926_2005.jpg
Full images:
http://pereplet.sai.msu.ru/nauka/i12.jpg
http://pereplet.sai.msu.ru/nauka/i12a.jpg
http://pereplet.sai.msu.ru/nauka/i12b.jpg
This work is supported by RFFI 04-02-16411 grant.
This message can be cited.
Mailto: lipunov@sai.msu.ru