GCN Circular 16853
Subject
GRB 140928A: LCO-Cerro Tololo further observations
Date
2014-09-30T10:36:59Z (10 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi (U. Ferrara), D. Kopac, C. Mundell (LJMU),
S. Dichiara (U. Ferrara) on behalf of a large collaboration report:
Using the Las Cumbres Observatory Global Telescope Network (LCOGTN) 1-m
telescope in Cerro Tololo (Chile), we re-observed Fermi GRB 140928A
(Desiante et al., GCN 16847; von Kienlin and Meegan GCN 16850)
in the r' filter starting on September 30, 07:14:36 UT, i.e. ~1.86
days after the Fermi trigger time.
The optical afterglow (Varela et al., GCN 16849; Kopac et al. GCN 16851)
is still clearly detected with R = 21.2 +/- 0.1 mag at a mid time
of 1.88 days post burst (total exposure of 1680 s).
The magnitude is calibrated against nearby USNO-B1 stars.
A comparison with our previous report (Kopac et al.) suggests an
average power-law decay index alpha = 1.2 +- 0.2.