TITLE:   GCN CIRCULAR
NUMBER:  15642
SUBJECT: GRB 131231A: afterglow confirmation from the NOT
DATE:    13/12/31 23:02:02 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>

D. Malesani, D. Xu (DARK/NBI), I. R. Losada (Stockholm), F. Duval 
(Stockholm), report on behalf of a larger collaboration:

We observed the afterglow candidate of GRB 131231A (Sonbas et al., GCN 
15640; Xu et al., GCN 15641) using the 2.56m Nordic Optical Telescope 
(NOT) equipped with MOSCA. Observations started at 22:05:40 UT on 2013 
Dec 31 (i.e., 17.3 hr after the Fermi trigger).

The afterglow candidate noted by Xu et al. (GCN 15641) has decayed to 
R=18.6, using the same calibration. We thus suggest that this source is 
very likely the afterglow of GRB 131231A. The coordinates of the 
afterglow can be refined to

R.A. = 00:42:21.665
Dec. = -01:39:10.61

with an error of 0.3".

We also wish a happy new year to everyone.