GCN Circular 11852
Subject
GRB 110328A / Swift J164449.3+573451: Mondy optical observations
Event
Date
2011-03-31T16:37:26Z (15 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), A. Volnova (SAI MSU), E. Klunko (ISTP) on behalf of
larger GRB follow up collaboration report:
We continue observation (Volnova et al. GCN 11837) of the field of GRB
110328A / Swift J164449.3+573451 (Cummings et al. GCN 11823) with AZT-33IK
telescope of Sayan observatory (Mondy). Several series of images in R- band
were taken on March 28 an 29. In the first epoch we clearly detect the
optical counterpart (Cenko et al. GCN 11827, Leloudas et al. GCN 11830),
while we do not detect it in the second epoch. The photometry below is based
on the USNO-A2.0 star 1425-08596694 assuming R=16.6. The first column
represents the time since first Swift trigger (Cummings et al. GCN 11823).
T0+ Filter, Exposure, OT mag., UpperLimit (3 sigma)
(mid, d) (s)
0.08944 R 6420 21.50 +/- 0.11 23.7
1.25258 R 870 n/d 22.9
Based on the above photometry we tentatively suggest the variability of the
optical counterpart between the two epochs. However the more precise
calibration of the field stars are necessary to make a definite conclusion
about variability.
[GCN OPS NOTE(30apr11): Per author's request, Elunko was changed to Klunko.]