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GCN Circular 29654

GRB 210306A: HCT optical upper limit
2021-03-13T04:44:34Z (3 years ago)
Harsh Kumar at Indian Inst of Tech,Bombay <>
H. Kumar (IITB), A. Dutta (IIA), R. Gupta (ARIES), V. Bhalerao (IITB), G.
C. Anupama (IIA), S. Barway (IIA), D.K. Sahu (IIA),  A. Kumar (ARIES),
Dimple (ARIES), A. Ghosh (ARIES), S. B. Pandey (ARIES), and K. Misra
(ARIES) report:

We observed GRB 210306A detected by Swift Burst Alert Telescope (V. D'Elia
et. al., GCN 29597) and optical afterglow confirmed by Alan M. Watson et.
al., (GCN 29598) with the 2.0m Himalayan Chandra Telescope (HCT) of the
Indian Astronomical Observatory. We obtained 6 exposures of 300 sec each in
the Bessell R filter. We did not detect the afterglow in our stacked image.
The photometric upper limit is:


 JD (mid) | T_mid-T0(hrs) | Filter | Lim_mag (5-sigma) |


2459282.110905 | 58.76 | Bessell R | > 23.22 |


The magnitudes are in the AB system of magnitude calibrated against PanSTARRS
(Flewelling et al., 2018) using Lupton's transformation equations available
The magnitudes are not corrected for galactic extinction.

These observations were carried out under the ToO program HCT-2021-C1-P2.
We thank the HCT staff for their support during the observations. The
Indian Astronomical Observatory is operated by the Indian Institute of
Astrophysics, Bengaluru, India.
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