[vsnet-grb-info 7766] GRB 090424: optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  9320
SUBJECT: GRB 090424: optical observations
DATE:    09/05/04 00:21:25 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

V. Rumyantsev, K. Antoniuk (CrAO), A. Pozanenko (IKI) report on behalf of 
larger GRB follow-up collaboration:

We observed the afterglow (Cannizzo et al. GCN 9223; Yuan GCN 9224) of  the 
Swift GRB 090424  (Trigger 350311; Cannizzo et al., GCN 9223) in R filter on 
Apr. 24   (18:25:36 -- 19:23:38) and  Apr. 26 (19:57:14 -- 21:01:01) with 
AZT-11 telescope of CrAO.  We  detect the afterglow in  combined images of 
both epochs. Astrometry of the afterglow is RA(J2000):  12 38 05.1 
Dec(J2000): +16 50 14.72   with uncertainty of 0.5 arcsec.
Preliminary photometry of combined images is based on  USNO-B1.0 
1068-0228255  star  RA=12:38:02.33  Dec=+16:51:10.0  is  following:

T0+     Filter, Exposure, mag.,     err.
(d)             (s)

0.1972 R 20x180 19.27  +/-0.06
2.2628 R 20x180 21.0   +/-0.2

The photometry is contaminated with possible host galaxy (Evans et al. GCN 
9226).

The combined image of the Apr. 24 observation can de found at
http://grb.rssi.ru/GRB090424/GRB090424_AZT-11_R.gif