GCN Circular 32078
Subject
GRB 220521A: NOT optical afterglow detection
Event
Date
2022-05-22T00:09:27Z (4 years ago)
From
Daniele B Malesani at Radboud U <d.malesani@astro.ru.nl>
D. B. Malesani (Radboud Univ. and DAWN/NBI) and T. Pursimo (NOT) report
on behalf of more people:
We observed the field of GRB 220521A (Dichiara et al., GCN 32076) with
the Nordic Optical Telescope (NOT) equipped with the ALFOSC imager. In a
300-s exposure beginning on 2022 May 21.983 UT (0.248 hr after the GRB),
we detect a new object consistent with the UVOT-enhanced X-ray position
(Evans, GCN 32077), at J2000 coordinates:
RA = 18:20:55.13
Dec = +10:22:20.5
Calibration is against the Gaia catalog, with an expected uncertainty <
0.3".
Photometry against nearby Pan-STARRS calibrators yields r = 21.06 +-
0.03 AB. Given the consistency with the X-ray position and the lack of
detection in the Pan-STARRS archival images, we conclude that this
source is the optical afterglow of GRB 220521A.