GCN Circular 10783
Subject
GRB 100418A: CrAO optical observations
Event
Date
2010-05-19T19:25:13Z (16 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
V. Rumyantsev (CrAO), A. Pozanenko (IKI) report on behalf of larger GRB
follow-up collaboration:
We observed the field of the Swift GRB 100418A (Marshall et al. GCN 10612)
with Shajn telescope of CrAO between (UT) May, 14 21:07 -- 22:48 under
photometric weather conditions and mean seeing of about 2 arcsec.
The preliminary photometry of the afterglow+host in a stacked image based on
USNO-B1.0 star 1014-0271368 (RA(J2000) = 17:05:26.42 Dec(J2000)=
+11:27:32.9) assuming R=17.32 is following:
T0+ Filter, Exposure, mag.
(mid, d) (s)
26.0332 R 90x60 21.86 +/-0.06
The photometry is compatible with R-magnitude reported by Perley et al, GCN
10727 (R=21.85+/-0.05 at 17.739 days) and still brighter than assumed
R-magnitude of the normal type of host galaxy (SDSS based ugriz-> R
conversion) which cannot be explained solely by afterglow contribution
fading steeper than power law with decay index of .~0.8.