[vsnet-grb-info 27407] GRB 210212A: 1.3m DFOT Optical upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29510
SUBJECT: GRB 210212A: 1.3m DFOT Optical upper limit
DATE:    21/02/15 18:26:17 GMT
FROM:    Rahul Gupta at ARIES, India  <rahulbhu.c157 at gmail.com>

Rahul Gupta,  A. Kumar, Dimple,  A. Ghosh, A. Aryan, B. Kumar, S. B.
Pandey, and K. Misra (ARIES) report:

We observed the field of Swift detected GRB 210212A (Troja et al., GCN
29487) with 1.3m Devasthal Fast Optical Telescope (DFOT) located at
Devasthal observatory of Aryabhatta Research Institute of
Observational Sciences (ARIES), India. The observations were started
on 2021-02-13 at 13:54:09 UT i.e. ~ 1.4 days after the BAT trigger. We
have taken multiple frames having an exposure time of 180 s in the R
filter. We did not detect any optical afterglow candidate within the
Swift/XRT enhanced position (Beardmore et al., GCN 29489).


We obtain the following 3-sigma upper limit in the stacked image.


Date Start_UT T_start-T0 (days) Filter  Exp time (s)  Limiting Magnitude

======================================================
2021-02-13 13:54:09   ~1.4          R   180*15      > 22.4



The magnitude is not corrected for the Galactic extinction in the
direction of the burst. Photometric calibration is performed using the
standard stars from the USNO-B1.0 catalogue.

This circular may be cited.