TITLE:   GCN CIRCULAR
NUMBER:  33189
SUBJECT: GRB 230116D: Sintez-Newton/CrAO optical observations
DATE:    23/01/17 19:01:13 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

S. Belkin (IKI, HSE), S. Nazarov (CrAO),  A. Pozanenko (IKI),  N. Pankov 
(HSE, IKI) report on behalf of GRB IKI FuN:

We observed the optical afterglow (Zhu et al., GCN 33177; Nazarov  et 
al., GCN 33178; Moskvitin et al. GCNs 33179, 33187; Swain et al., GCN 
33182) of GRB 230116D (Sonbas et al., GCN 33176) with Sintez-Newton 
telescope of CrAO observatory.  Observation started on 2023-01-16 (UT) 
21:21:41. The series consist of images with an exposure of 120 s in 
Clear filter. Preliminary photometry of the stacked images is following

Date UT-start       Exptime Filter t-T0     OT     Err     UL
2023-01-16 21:23:55 35*120  Clear  0.03764  19.82  0.08    22.5
2023-01-16 22:44:52 33*120  Clear  0.09245  19.97  0.16    21.9

Ref.stars
USNO-B1.0
RA DEC R2

06:34:04.9708800 +49:53:05.863200 15.61
06:34:38.7820800 +49:49:22.972800 16.29
06:34:57.9967200 +49:53:01.932000 16.94
06:34:24.5268000 +49:47:49.801200 15.68