TITLE: GCN CIRCULAR NUMBER: 33540 SUBJECT: GRB 230328B: Nanshan/NEXT 2nd optical observation DATE: 23/03/30 01:53:10 GMT FROM: Dong Xu at NAOC/CAS dxu@nao.cas.cn
T.H. Lu, S.Q. Jiang, S.Y. Fu, X. Liu (NAOC), Z.P. Zhu (NAOC, HUST), D. Xu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report:
We observed the field of GRB 230328B detected by Swift (Gropp et al., GCN 33527) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained 12x300 s frames in the Sloan r-band, starting at 14:49:11 UT on 2023-03-29 (i.e., 23.9 hr after the BAT trigger).
The optical afterglow (e.g., Pankov et al., GCN 33528; Belkin et al., GCN 33530; Lu et al., GCN 33534; Catapano et al., GCN 33535; Suresh et al., GCN 33536; Adami et al., GCN 33537; Gompertz et al., GCN 33538; Komesh et al., GCN 33539) is not detected in our stacked image. Preliminary photometric result is as follows:
T_mid-T0 (hr) Filter Upper limit(3-sigma) 24.42 r >21.0
calibrated with the nearby PanSTARRS field and not corrected for Galactic extinction.