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GCN Circular 29180

GRB 201223A: AROMA-N Optical Observation
2020-12-27T22:15:11Z (3 years ago)
Takanori Sakamoto at AGU <>
M. Nakamura, K. Hasuda, T. Sakamoto (AGU)

We observed the field of GRB 201223A detected by Swift
(Gropp et al., GCN Circ. 29158) with the 14-inch AGU Robotic
Optical Monitor for Astrophysical object - Narrow (AROMA-N)
located at the Sagamihara campus of Aoyama Gakuin University.
58 images of 60 sec exposures were taken in the R filter
starting from December 23 18:04:02 (UT) about 5.6 minutes
after the trigger and stopped on December 23 19:16:09 (UT).
We do not detect the optical afterglow both in the individual
images and the stacked image.  The estimated five sigma
upper limit of the combined image (total exposure of 3480 sec)
is ~17.3 mag using the USNO-B1 catalog.
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