TITLE: GCN CIRCULAR NUMBER: 31353 SUBJECT: GRB 220101A: Xinglong-2.16m photometry and spectroscopy DATE: 22/01/01 15:51:07 GMT FROM: Dong Xu at NAOC/CAS S.Y. Fu (NAOC), Z.P. Zhu (NAOC, HUST), D. Xu, X. Liu, S.Q. Jiang (NAOC) report on behalf of a larger collaboration: We observed the field of GRB 220101A detected by Swift (Tohuvavohu et al., GCN 31347) and Fermi (Arimoto et al., GCN 31350) using the Xinglong-2.16m telescope equipped with the BFOSC camera. Observations were carried out starting at 09:50:07 UT on 2022-01-01. We firstly obtained 4x300 s frames in each of the B, V, R and I bands, and then 2x1800 s spectroscopy covering ~3800 - 8800 AA. The optical afterglow of the burst (Tohuvavohu et al., GCN 31347) is clearly detected in each of our stacked images in the V, R and I bands, but no in the B band. Preliminary photometry is as follows: Tmid-T0 (hr) Mag MagErr Filter 5.55 >21.43 N/A B 5.45 19.86 0.06 V 5.36 18.65 0.02 R 5.27 17.34 0.01 I The spectrum is in low resolution and rather low S/N. However, a broad absorption feature is evident centering at ~ 6820 AA, which can interpreted as Ly_alpha absorption. Besides Ly_alpha, other weak lines such as Si II, C II, Si IV are also detected at the common redshift of z = 4.61. We thus conclude that z = 4.61 is likely the redshift of the GRB. We thank the great support of the Xinglong-2.16m staff, in particular Junjun Jia, Yinan Zhu, Aiying Zhou, and Jie Zheng.