GCN Circular 19651
Subject
GRB 160625B: RTT150 optical observations
Event
Date
2016-07-04T13:42:20Z (10 years ago)
From
Rodion Burenin at IKI, Moscow <rodion@hea.iki.rssi.ru>
I. Bikmaev, E. Irtuganov, N. Sakhibullin (KFU/AST),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
I. Khamitov, H. Kirbiyik (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.)
report:
We observed field of Fermi GRB 160625B (Dirirsa et al. GCN 19580) at
the position of optical afterglow (Troja et al. ,GCN 19588) with
Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National
Observatory, Turkey) using the TFOSC instrument.
We obtained series of Rc exposures in June 30 / July 01(6 frames x 600
sec, UT = 00:21 - 01:30 ), in July 01 / 02 (4 frames x 900 sec, UT =
00:36 - 01:42), in July 02 / 03 (6 frames x 900 sec, UT = 23:49 -
01:29), and in July 03 / 04, 2016, (14 frames x 600 sec, UT = 22:50 -
01:39). The optical transient (Troja et al. GCN 19588; Oates et
al. GCN 19589; Kuroda et al. GCN 19599; Xu et al. GCN 19600; D'Elia et
al. GCN 19601; Watson at al. GCN 19602; Karpov et al. GCN 19603;
Mazaeva et al. GCN 19605, 19620; Moskvitin et al. GCN 19611;
Gorbovskoy et al. GCN 19612; Batsch et al. GCN 19615; Cobb et al. GCN
19616; Guidorzi et al. GCN 19640; Valeev et al. GCN 19642) is clearly
detected in each images.
Using USNO-B1 0969-0608410 star at RA,DEC = 308.580912 +06.909881
(J2000.0) with R = 16.73 mag as a reference we estimated the
Rc-magnitudes of the afterglow in stacked images:
T-T0, Mag., Mag.err
days
5.09 20.69 +- 0.03
6.10 20.96 +- 0.04
7.08 21.04 +- 0.03
8.06 21.24 +- 0.04
RTT-150 data show that OT is fading at approximately the same power
law rate as it was observed earlier.