TITLE: GCN CIRCULAR NUMBER: 28846 SUBJECT: GRB 201103B (ZTF20acozryr/AT2020yxz): Nanshan/NEXT-0.6m optical observations DATE: 20/11/06 02:36:07 GMT FROM: Dong Xu at NAOC/CAS D. Xu (NAOC), Z.P. Zhu (NAOC, HUST), S.Y. Fu, X. Liu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We observed the optical transient, ZTF20acozryr/AT2020yxz, an likely orphan GRB optical afterglow when discovered by ZTF (Coughlin et al., GCN 28841) and later confirmed by the IPN localisation as the optical afterglow of GRB 201103B (Svinkin et al., GCN 28844), using the NEXT-0.6m optical telescope located at Nanshan, Xinjiang, China. Observations started at 17:33:06 UT on 2020-11-05 and a series of 120s exposures were obtained in the Sloan r-filter. Considering the IPN trigger time, 18:06:47 UT on 2020-11-03, as the onset of the burst, preliminary photometry results are as follows: T_mid_obs (UT) T_mid_grb(day) Mag MagErr 2020-11-05T17:43:35 1.984 20.5 0.3 2020-11-05T18:31:28 2.017 20.8 0.2 calibrated with nearby PS1 stars. Compared with the ZTF photometry, such a decay is consistent with that of a conventional GRB optical afterglow.