TITLE: GCN CIRCULAR NUMBER: 31373 SUBJECT: GRB 220101A: TNG NIR afterglow detection DATE: 22/01/03 12:20:15 GMT FROM: Paolo D'Avanzo at INAF-OAB P. D'Avanzo (INAF-OAB), A. Melandri, S. Covino (INAF-OAB), V. D'Elia (ASI-SSDC), M. De Pasquale (Univ. Messina), D. B. Malesani (Radboud), S. Piranomonte (INAF-OAR), V. Lorenzi, C. Padilla (INAF-TNG), Paolo Giacobbe (INAF-OATO) on behalf of the CIBO collaboration report: We observed the field of GRB 220101A (Tohuvavohu et al., GCN Circ. 31347; Arimoto et al., GCN Circ. 31350; Ursi et al., GCN Circ. 31354; Lesage & Meegan, GCN Circ. 31360) with the Italian 3.6m TNG telescope equipped with the near-infrared camera NICS. A series of images were obtained with the J, H, K filters on 2022-01-02 from 20:21:15 UT to 21:57:47 UT (i.e. at a mid time of about 1.67 days after the burst). A source is clearly detected in all bands at the optical and mm afterglow position (Kuin & Tohuvavohu, GCN Circ. 31351; Laskar, GCN Circ. 31372). From preliminary photometry we derive the following magnitude: J = 18.29 +/- 0.05 (Vega; calibrated against the 2MASS catalogue). We report the presence of a possibly extended source which lies about 1.8” North with respect to the NIR GRB afterglow. For this source we derive J ~ 20 mag (Vega). We note that this source is present in the CatWISE2020 catalogue (Marocco et al., 2021, ApJSS, 253, 22; arXiv:2012.13084).