GCN Circular 33192
Subject
GRB 230116D: SAO RAS further observations
Event
Date
2023-01-18T04:08:32Z (3 years ago)
From
Moskvitin Alexander at SAO RAS <mosk@sao.ru>
A. S. Moskvitin, O. I. Spiridonova and O. A. Maslennikova (SAO RAS),
report on behalf of the GRB follow-up team.
We observed the field of the GRB 230116D (Sonbas et al. GCN #33176)
with the SAO RAS 1-m telescope Zeiss-1000 + CCD-photometer in Rc band
on January 16/17 (21:55:22--00:36:40 UT) and 17/18 (21:42:43--23:31:38).
During the first night the optical afterglow (Zhu et al., GCN #33177;
Nazarov et al., GCN #33178; Moskvitin et al. GCNs #33179, #33187;
Swain et al., GCN #33182; Belkin et al., GCNs #33189, #33190, #33191)
was clearly detected in individual frames and shows complex behaviour.
t-T0, h R_mag +/- err exp, s
0.844 19.967 +/- 0.070 300
0.948 19.888 +/- 0.068 300
1.045 19.874 +/- 0.066 300
1.138 19.818 +/- 0.063 300
1.233 19.674 +/- 0.057 300
1.332 19.595 +/- 0.051 300
1.432 19.701 +/- 0.055 300
1.526 19.668 +/- 0.056 300
1.623 19.779 +/- 0.062 300
1.717 19.764 +/- 0.063 300
1.820 19.728 +/- 0.058 300
1.924 19.626 +/- 0.055 300
2.022 19.539 +/- 0.052 300
2.130 19.709 +/- 0.064 300
2.226 19.798 +/- 0.070 300
2.346 19.870 +/- 0.078 300
2.444 19.976 +/- 0.083 300
2.644 20.021 +/- 0.086 300
2.835 20.065 +/- 0.066 2 x 300
3.041 20.032 +/- 0.063 2 x 300
3.241 20.138 +/- 0.062 2 x 300
3.441 20.223 +/- 0.075 2 x 300
We also obtained 17 x 300 images in Rc band during the second night.
The OT is detected in the stacked frame with the brightness of
R = 22.9 +/- 0.2 (t-T0 = 25.541h = 1.064d) which is in agreement with
upper limit reported by Strausbaugh & Cucchiara (GCN #33188).
Preliminary photometry is based on R2 magnitudes of nearby USNO-B1 stars.