[vsnet-grb-info 14890] GRB 140423A: RTT150 optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16185
SUBJECT: GRB 140423A: RTT150 optical observations
DATE:    14/04/29 19:47:26 GMT
FROM:    Rodion Burenin at IKI, Moscow  <rodion at hea.iki.rssi.ru>

I. Bikmaev (KFU/AST), I. Khamitov (TUG),
S. Melnikov, N. Sakhibullin (KFU/AST),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
H. Kirbiyik (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.)

report:

The field of the optical afterglow of GRB 140423A (Sonbas et al., GCN
16142) was observed with Russian-Turkish 1.5-m telescope (RTT150,
Bakirlitepe, TUBITAK National Observatory, Turkey) using the TFOSC
instrument.

We obtained series of 300 sec exposures in B and Rc filters with mean
time in April 24, 00:34 UT (B) and April 24, 01:58 UT (Rc). The
afterglow is clearly detected in combined images.

Using the USNO-B1 (1398-0233739) star at RA = 13:09:13.1, DEC =
+49:53:11, with B1_mag = 16.70, R1_mag = 14.76 as a reference, we
estimated the B and R-magnitudes of the afterglow:

Filter    T-T0, hours   Mag. +/- Mag.err

B         16.03         23.21 +/- 0.09
Rc        17.43         21.29 +/- 0.06