[vsnet-grb-info 10422] GRB 110402A: NOT afterglow confirmation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11859
SUBJECT: GRB 110402A: NOT afterglow confirmation 
DATE:    11/04/02 02:51:06 GMT
FROM:    Giorgos Leloudas at Dark Cosmology Centre  <giorgos at dark-cosmology.dk>

G. Leloudas (DARK/NBI), D. Xu (WIS), P. Jakobsson (U. Iceland), M.
Bayliss (U. Chicago/KICP), report on behalf of a larger collaboration:

We observed the field of GRB 110402A (Ukwatta  et al., GCN 11857) with
the Nordic Optical Telescope (La Palma, Spain) equipped with MOSCA.

Observations started at 01:26:09.0 UT (73.9 mins after the GRB).
We obtained 3x300 s in the R filter.
We detect a transient within the XRT error circle consistent with the
position reported in Mundell et al. (GCN 11858).

Between the 1st and 3rd exposures, the optical transient shows  
marginal decay from 21.10 +- 0.02  to 21.17 +- 0.04 mag, calibrated  
with respect to the USNO
B1 star 1512-0199231 (R1= 16.71 mag).

Since the object has also faded by 0.3 mag with respect to GCN 11858,  
we suggest that this is the afterglow of GRB 110402A.