TITLE: GCN CIRCULAR NUMBER: 31363 SUBJECT: GRB 220101A: Asiago spectroscopic and photometric detection DATE: 22/01/02 01:19:25 GMT FROM: Lina Tomasella at INAF,Padova L. Tomasella (INAF-OAPadova), E. Brocato (INAF-OAAbruzzo), M. D’Onofrio (DFA UniPd), E. Cappellaro, S. Benetti (INAF-OAPadova) On behalf a larger collaboration report: We observed the optical counterpart of GRB 220101A (Tohuvavohu et al., GCN 31347; Arimoto et al., GCN 31350) using the Asiago Copernico and Schmidt Robotic telescopes (INAF-OAPadova). The Copernico Telescope is equipped with the AFOSC spectrograph. A low S/N spectrum was obtained starting on 2022-01-01 UT 22:21:03, covering the wavelength range 3400-8200 AA. As reported by Fu at al., GCN 31353 and by Fymbo et al., GCN 31359, a deep, broad feature is detected around 6800 AA, interpreted as the damped Lyman alpha. Other narrow absorption lines are also detected, which allow to confirm the GRB redshift z = 4.61 The afterglow was observed starting on 2022-01-01 between 22:01 and 22:05 UT using Copernico Telescope with BV filters and with gri Sloan filters (two series) using Schmidt 67/92 Robotic Telescope between 22:08 and 22:25 UT. The afterglow is detected in several individual images. We measure V-Bessel = 20.48 +/- 0.1 mag in the Copernico image taken at UT 22:01. The spectral and photometric analysis results presented above are preliminary; data analysis is ongoing.