GCN Circular 13236
Subject
GRB 120404A: optical observations in Mondy observatory
Date
2012-04-08T14:58:38Z (13 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A.Volnova (SAI MSU), E. Klunko (ISTP), A. Pozanenko (IKI) on behalf of
larger GRB follow up collaboration report:
We observed the field of the Swift GRB 120404A (Stratta et al., GCN 13208)
with AZT-33IK telescope of Sayan observatory (Mondy). We took several images
in R-filter of 60 s exposure on Apr. 04, starting (UT) 14:31:21. We clearly
detected optical afterglow (Stratta et al., GCN 13208; Guidorzi et al., GCN
13209) in single images. A preliminary photometry of combined images is
based on nearby USNO-B1.0 stars:
t_start, t-t0 (mid), filter exp., OT, err
(UT) d s
14:31:21 0.07142 R 5x60 18.24 0.05
14:37:26 0.07564 R 5x60 18.36 0.04
14:42:30 0.07916 R 5x60 18.40 0.05
14:47:34 0.08268 R 5x60 18.36 0.07
14:52:37 0.08619 R 5x60 18.59 0.07
14:58:42 0.09041 R 5x60 18.59 0.04
15:03:46 0.09393 R 5x60 18.77 0.12
15:08:50 0.09920 R 10x60 18.76 0.06
15:19:58 0.10694 R 10x60 18.95 0.06
15:30:06 0.11432 R 10x60 18.94 0.08
15:41:14 0.12171 R 10x60 19.00 0.08
15:51:21 0.12908 R 10x60 19.30 0.09
Our photometry suggests bumpy light curve of the afterglow during our
observations.