GCN Circular 9329
Subject
GRB 090418A: optical observation
Date
2009-05-09T20:15:43Z (15 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
V. Rumyantsev, E. Pavlenko(CrAO), A. Pozanenko (IKI) report on behalf of
larger GRB follow-up collaboration:
We observed the afterglow of the Swift GRB 090418A (Mangano et al., GCN
9149) in I-filter on Apr. 20 (UT) 02:34:12 - 04:08:27
and in R-filter on Apr. 20 (UT) 21:03:05 - 22:49:20 with Shajn telescope of
CrAO. We clearly detect afterglow in both epochs in stacked images.
Preliminary photometry of Apr. 20 as well a photometry in V-filter of Apr.
18 observations (Pavlenko et al. GCN 9179) is following:
T0+ Filter, Exposure, mag., err. UL Seeing
(d) (s)
0.5476 V 17x60 22.3 +/- 0.2 23.2 1.9"
2.4507 R 70x60 22.8 +/- 0.1 24.4 1.9"
Due to worse seeing (2.4") on Apr. 20 (UT) 02:34:12 - 04:08:27 the afterglow
is evidently contaminated with nearby galaxy and photometry will be reported
later. The photometry of Apr. 20 (UT) 21:03:05 - 22:49:20 also should be
treated with caution due to possible contamination.