GCN Circular 20516
Subject
GRB 170121B: AbAO optical observations
Date
2017-01-24T17:41:03Z (8 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Pozanenko (IKI), R. Inasaridze (AbAO), A. Volnova
(IKI), V. Ayvazian (AbAO), O.Kvaratskhelia (AbAO), G. Inasaridze (AbAO),
I. Molotov (KIAM), report on behalf of larger GRB follow-up collaboration:
We observed the field of optical transient reported by Lipunov et al. (GCN
20502) as a possible candidate of the Fermi/GBM GRB 170121B (Hamburg et al.
GCN Circ. 20505) and XRT afterglow candidate reported by Sbarufatti et
al. (GCN 20510) with AS-32 (0.7m) telescope of Abastumani Observatory
starting on Jan., 23 (UT) 16:14:49. We obtained several unfiltered images
of the field. We do not find any source at coordinates of the optical
transient (Lipunov et al., GCN 20502). Within XRT error circle (Sbarufatti
et al., GCN 20510) we find the source which is also presented in DSS2 and
USNO-B1.0 as the star USNO-B1.0 0807-0048671 (magnitudes R1 = 17.94, R2 =
17.07). Preliminary photometry of the source and the field of the optical
transient (Lipunov et al., GCN 20502) is following
Date UT start t-T0 Filter Exp. OT Err UpLim (3 sigma)
(mid, days) (s)
2017-01-23 16:14:49. 2.09866 CR 60*60 17.76 0.07 22.9
Photometry is based on nearby USNO-B1.0 stars (R2 magnitudes)
USNO-B.1_id R2
0807-0048576 16.37
0806-0049543 18.47
0807-0048525 17.28
0807-0048536 17.23
0806-0049637 15.57
0807-0048826 15.71
0807-0048833 15.41
0807-0048816 17.22