[vsnet-grb-info 28567] GRB 210820A: NOT optical upper limit
GCN Circulars
gcncirc at capella2.gsfc.nasa.gov
Sat Aug 21 16:31:13 JST 2021
TITLE: GCN CIRCULAR
NUMBER: 30670
SUBJECT: GRB 210820A: NOT optical upper limit
DATE: 21/08/21 07:30:12 GMT
FROM: Dong Xu at NAOC/CAS <dxu at nao.cas.cn>
Z.P. Zhu (NAOC, HUST), D. B. Malesani (DTU space), L. Izzo (DARK/NBI),
J.P.U. Fynbo (DAWN/NBI), D. Xu (NAOC), R. Clavero (NOT) report on behalf
of a larger collaboration:
We observed the field of GRB210820A (Beardmore et al., GCN30664) using
the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. We
obtained 3x200s frames in the Sloan r- filter, starting at 00:49:56 UT
on 2021-08-21 (i.e., ~ 7.29 hr after the BAT trigger).
No optical source is detected in our stacked image at the Swift/UVOT
position (Beardmore et al., GCN 30664), down to a limiting magnitude of
r~22.2, calibrated with the nearby PanSTARRS field.
More information about the vsnet-grb-info
mailing list