GCN Circular 29956
Subject
GRB 210506A: Nanshan/NEXT optical upper limit
Date
2021-05-07T03:12:02Z (4 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
S.Y. Fu (NAOC), Z.P. Zhu (NAOC, HUST), X. Liu, D. Xu (NAOC), X. Gao
(Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:
We observed the field of GRB 210506A (Tohuvavohu, DeLaunay & Kennea, GCN
29947) using the NEXT-0.6m telescope located at Nanshan, Xinjiang,
China. We obtained 9x300 s frames in the Sloan r-band, starting at
15:17:27 UT on 2021-05-06, i.e., 14.63 hr after the BAT trigger.
No credible optical source is detected in our stacked image at the
position of the XRT source #3 that lies in the BAT error circle (ref.
https://www.swift.ac.uk/ToO_GRBs/00021430/ and Evans, GCN 29949), down
to a limiting magnitude of r~21.7, calibrated with the nearby PanSTARRS
field.