GCN Circular 33608
Subject
GRB 230409B: Mondy optical upper limit
Date
2023-04-12T23:21:33Z (a year ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
S. Belkin (IKI), E. Klunko (ISTP), A. Pozanenko (IKI), N. Pankov (HSE)
report on behalf of GRB IKI FuN:
We observed the field of Swift GRB 230409B (Beardmore et al., GCN 33592)
with AZT-33IK telescope of Mondy observatory in R-filter on 2023-04-09
starting (UT) 14:52:05. We do not detect the optical counterpart (Kuin
et al., GCN 33595) within the enhanced Swift/XRT error box (Evans et
al., GCN 33594). Preliminary photometry of a stacked image is following
Date UT start t-T0 Exp. Filter OT Err. UL(3sigma)
(mid, days) (s)
2023-04-09 14:52:05 0.42231 26*60 R n/d n/d 20.5
The photometry is based on nearby USNO-B1.0 stars.
USNO-B1.0
RA DEC R2
21:58:01.9195200 +52:49:21.982800 15.15
21:58:13.7054400 +52:48:57.002400 15.56
21:57:54.5028000 +52:50:57.080400 15.95
The upper limit does not contradict result reported by Adami et al. (GCN
33607).