GCN Circular 29094
Subject
GRB 201209A: Mondy optical observations, afterglow confirmation
Date
2020-12-20T10:46:03Z (3 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
N. Pankov (HSE), A. Pozanenko (IKI), A. Volnova (IKI), S. Belkin (IKI),
E. Klunko (ISTP) report on behalf of IKI GRB FuN:
We observed the field of GRB 201209A (Gropp et al., GCN 29005) with
AZT-33IK telescope of Sayan observatory (Mondy) starting on Dec. 09 (UT)
11:41:13 (i.e. 0.28 days) and next epochs later. We detected a weak
source within enhanced XRT position (Goad et al., GCN 29005) at ~1.4
days after GRB 201209A trigger and not detected in other epochs. Thus
we confirm the optical afterglow detection on 0.321 days at R = 22.05
+/- 0.16 (Zhu et al. GCN 29013).
Preliminary photometry of the field and afterglow is following
Date UT start t-T0 Filter Exp. OT Err. UL(3sigma)
(mid, days) (s)
2020-12-09 11:41:13 42*120 R 0.27873 n/d n/d 21.7
2020-12-10 14:26:13 45*120 R 1.39332 23.4 0.3 23.5
2020-12-12 11:14:21 39*120 R 3.25868 n/d n/d 22.2
2020-12-13 12:03:41 38*120 R 4.26307 n/d n/d 22.9
The photometry is based on nearby USNO-B1.0 stars.