GCN Circular 32355
Subject
GRB 220708B: Nanshan/NEXT optical upper limits
Date
2022-07-09T03:18:20Z (2 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
S.Q. Jiang (NAOC), Z.P. Zhu (NAOC,HUST), S.Y. Fu , X. Liu, D. Xu (NAOC),
X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:
We observed the field of GRB 220708B detected by Swift/BAT-GUANO
(Tohuvavohu et al., GCN 32345) using the NEXT-0.6m telescope located at
Nanshan, Xinjiang, China. We obtained 10x200 s frames in the Sloan
r-band and 9x200 s frames in Sloan z-band, starting at 19:15:57.859 UT
on 2022-07-08,i.e.,17.15 hr after the BAT trigger.
No optical source is detected in our stacked images at the XRT
afterglow position (Osborne et al., GCN 32350), with upper limits as
follows:
T_mid-T0 (hr) Filter Upper limit(3-sigma)
17.42 r >21.60
17.96 z >19.54
calibrated with the nearby PanSTARRS field and not corrected for
Galactic extinction.