GCN Circular 31844
Subject
GRB 220403B: Mondy optical upper limit
Event
Date
2022-04-06T16:37:01Z (4 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
N. Pankov (HSE), A. Pozanenko (IKI), E. Klunko (ISTP), S. Belkin (IKI)
report on behalf of GRB IKI FuN:
We observed the field of GRB 220403B (Klingler et al., GCN 31820)
with AZT-33 telescope of Mondy observatory starting on April, 05 (UT)
15:00:54. We do not detect the optical afterglow (Klingler et al.,
GCN 31820; Jelinek et al., GCN 31821; Zhu et al., GCN 31823; Rossi
et al., GCN 31826; Pankov et al., GCN 31837; Hu et al., GCN 31841; see
also early upper limits in Lipunov et al., GCN 31825; Grossan et al.,
GCN 31830) in the combined image.
Preliminary photometry of the combined image is following
Date, UT start, t-T0, Exp., Filter, OT, Err, UL(3 sigma)
(mid, days)
2022-04-05 15:00:54 1.77723 20*120 R n/d n/d 23.2
The photometry is based on nearby USNO-B1.0 stars, R2 magnitude
USNO-B1.0_id R2
1791-0003982 16.77
1791-0003984 17.83