GCN Circular 29512
Subject
GRB 210212B (TF21aakruew/AT2021cwd): Assy optical observations
Date
2021-02-16T13:44:36Z (4 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), S. Belkin (IKI), V. Kim (FAI, Pulkovo Observatory),
Y. Aimuratov (FAI), M. Krugov (FAI), N.Pankov (HSE) report on behalf of
GRB IKI FuN
We observed the optical transient of ZTF21aakruew/AT2021cwd (Yao et al.,
GCN 29508) which is probably an afterglow of GRB 210212B (Svinkin et
al., GCN 29511) with AZT-20 telescope of Assy-Turgen observatory
starting on 2021-02-15 (UT) 17:33:23. The optical transient is
marginally detected in a stacked image in r'-filter.
Preliminary photometry of the object is following
Date UT start t-T0 Filter Exp. OT S/N Err. UL(3sigma)
(mid, days) (s)
2021-02-15 17:33:23 3.64231 r' 59*60 23.8 2.5 0.5 23.6
The photometry is based on nearby SDSS-DR12 stars
RA DEC r dr
10:24:36.66048 +11:35:29.6088 18.206 0.008
10:24:34.08528 +11:36:05.0220 17.486 0.006
10:24:47.98080 +11:38:11.0832 15.153 0.003
The midtime value (t-T0) given in the table above was counted from GRB
trigger of 2021-02-12 (UT) 02:37:57 (Svinkin et al., GCN 29511).
The power-law index of the light curve (alpha ~ 1.7) is consistent with
an afterglow after jet break. The light curve can be found in
http://grb.rssi.ru/GRB210212B/GRB210212B_LC.png