GCN Circular 29283
Subject
GRB 210104A: Assy continued optical observations, correction to GCN circ. 29265
Event
Date
2021-01-10T16:05:11Z (5 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
V. Kim (FAI, Pulkovo Observatory), S. Belkin (IKI), A. Pozanenko (IKI),
M. Krugov (FAI), Y. Aimuratov (FAI) report on behalf of GRB IKI FuN:
We continued observations of the GRB 210104A (Fermi GBM team, GCN 29232;
Troja et al., GCN 29233; Frederiks et al., GCN 29258; Cherry et al.,
GCN 29268) with AZT-20 telescope of Assy-Turgen observatory starting on
Jan. 05 (UT) 12:55:33 in r'-filter. We detect the optical afterglow
(Troja et al., GCN 29233; Xin et al., GCN 29235; Hu et al., GCN 29236;
Hosokawa et al., GCN 29237; Kim et al., GCN 29238, 29265; Lipunov et
al., GCN 29239; Horiuchi et al., GCN 29241; Breeveld et al., GCN 29247;
Zhu et al., GCN 29252; Paek et al., GCN 29254; Kumar et al., GCN 29257;
Smartt et al., GCN 29262; Romanov, GCN 29269; Anandagoda et al., GCN
29273; Gokuldass, GCN 29274; Mao et al., GCN 29275; Moskvitin et al.,
GCN 29277).
Preliminary photometry is following
Date UT start Filter Exp. OT(AB) Err. UL(3 sigma)
(s)
2021-01-06 15:18:17 r' 82*60 22.00 0.08 23.0
2021-01-09 17:22:22 r' 136*60 22.88 0.19 24.1
The photometry is based on nearby stars of PanSTARRS-PS1.
Observations are continuing.
We also report corrected date of observation reported in the GCN 29265.
The correct table of the GCN 29265 should be as follows
Date UT start Filter Exp. OT(AB) Err.
2021-01-05 15:35:27 r' 20*60 20.85 0.07
2021-01-05 16:20:20 r' 20*60 21.23 0.10
2021-01-05 17:05:11 r' 20*60 21.19 0.06