GCN Circular 30187
Subject
GRB 210610B: SAO RAS optical observations
Date
2021-06-11T03:16:36Z (3 years ago)
From
Moskvitin Alexander at SAO RAS <mosk@sao.ru>
A. S. Moskvitin (SAO RAS) on behalf of the GRB follow-up team report.
We observed the field of the GRB 210610B with the SAO RAS 1-m
telescope Zeiss-1000 + CCD-photometer in BVRc Johnson-Cousins filters.
The observations started on June 10, 20:21:53 UT, since half an hour
after the burst detection by the Swift/BAT (Page et al., GCN #30170).
We clearly detected the OT (Page et al., GCN #30170; Kumar et al.,
GCN #30174; Rumyantsev et al., GCNs #30175, #30178; Hu et al.,
GCN #30177; de Wet et al., GCN #30180; Romanov, GCN #30181;
Fynbo et al., GCN #30182) with the following brightness:
UT_mid T_mid-T0, h Exp., s Rc mag (+/- 0.01 mag)
20:22:03 0.510 20 16.15
20:32:40 0.687 60 16.43
20:48:12 0.946 60 16.75
21:19:20 1.448 60 17.13
21:28:10 1.612 60 17.22
21:53:21 2.032 60 17.26
22:13:03 2.360 60 17.19
22:36:03 2.743 180 17.17
23:04:20 3.215 120 17.20
23:52:38 4.020 120 17.19
The preliminary photometry is based on the USNO-A2.0 star
from GCN #30178 (Rumyantsev et al.).
Magnitudes were not corrected for MW extinction.