GCN Circular 31041
Subject
GRB 211023A: continued 1.3m DFOT Optical Observations and possible jet break
Date
2021-11-05T06:00:44Z (3 years ago)
From
Rahul Gupta at ARIES, India <rahulbhu.c157@gmail.com>
Rahul Gupta, S. B. Pandey, Amit Ror, Amit Kumar, Dimple, Ankur Ghosh, Amar
Aryan, Bhavya, and Kuntal Misra (ARIES) report:
We further observed the bright GRB 211023A (Fermi GBM Team 2021, GCN
30958; Lesage et al. 2021, GCN 30965; N. Di Lalla et al. 2021, GCN
30961; Ursi et al. 2021, GCN 30969; and Ridnaia et al. 2021, GCN
31022) with 1.3m Devasthal Fast Optical Telescope (DFOT) located at
Devasthal observatory of Aryabhatta Research Institute of
Observational Sciences (ARIES), India, starting on 2021-10-29 at
19:19:13 UT, i.e., ~ 6.26 days after the Fermi trigger. We obtained 24
and 18 frames having an exposure time of 300 sec in the R and I
filters, respectively. We detected the optical afterglow of GRB
211023A (Lipunov et al. 2021, GCN 30970; Zhirkov et al. 2021, GCN
30977; Kann et al. 2021, GCN 30982; Hu et al. 2021, GCN 30990; Belkin
et al. 2021, GCN 31004, 31018, 31020; Vinko et al. 2021, GCN 31008;
and Kumar et al. 2021, GCN 31023) in our stacked images of both the
filters. The preliminary photometric estimate of the afterglow in the
R filter is following :
Date Start UT T-T0 (mid, days) Filter Exp time (sec) Magnitude
=========================================================2021-10-29
19:19:13 ~6.28 R 300*24 22.58 +/- 0.33
Based on the preliminary photometry reported by using various
ground-based optical telescopes (Kann et al. 2021, GCN 30982; Hu et
al. 2021, GCN 30990; and Belkin et al. 2021, GCN 31004, 31018, 31020)
and our first epoch observations using 1.3m DFOT (Kumar et al. 2021,
GCN 31023