GCN Circular 15980
Subject
GRB 140311A: further NOT observations
Date
2014-03-13T10:30:24Z (10 years ago)
From
Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst <malesani@dark-cosmology.dk>
D. Malesani (DARK/NBI), P. D'Avanzo (INAF/Brera), Y. F. Martinez Osorio
(NOT and Univ. Uppsala), report on behalf of the CIBO collaboration:
We observed the optical afterglow of GRB 140311A (Racusin et al., GCN
15944; Xu et al., GCN 15947) with the Nordic Optical Telescope equipped
with ALFOSC. A total exposure of 24 min was secured in the SDSS i band.
At a mean epoch of March 13.043 UT (1.16 days after the GRB), the
optical counterpart is well detected with an AB magnitude i = 22.45 +-
0.08, calibrated to several nearby SDSS stars. The position of the
afterglow is (J2000):
RA = 13:57:13.29
Dec = +00:38:31.7
referenced to the USNO-B1 catalog (0.3" error).
Compared to the i-band value reported by Littlejohns et al. (GCN 15978),
our measurement implies a decay index alpha = 0.81 +- 0.10 (Fnu propto
nu^-alpha), consistent with the value reported by these authors.