TITLE: GCN GRB OBSERVATION REPORT NUMBER: 984 SUBJECT: GRB 010222 Kyoto optical observation DATE: 01/02/24 10:20:09 GMT FROM: Taichi Kato at Kyoto U GRB 010222 Kyoto optical observation M. Uemura, R. Ishioka, H. Iwamatsu, T. Kato, Kyoto Univ., and H. Yamaoka, Kyushu Univ., on behalf of VSNET-GRB collaboration report: We observed the field of GRB 010222 starting at Feb. 22, 12:16 UT, with 0.30-m Schmidt-Cassegren telescope (+ unfiltered CCD) at Kyoto University. The GRB was detected on the images. The following photometry has been obtained: mid UT total exp. delta mag detection level Feb. 22.534 (22.511-22.554) 2160s 3.09 (1.7 sigma) 22.852 (22.842-22.861) 1350s 4.61 (6.2 sigma) The magnitudes are relative to PG 1450+432 (V=14.50). By assuming Rc = 14.70 for this star (Henden et al.), the observed magnitudes are 17.8 and 19.3 respectively. The low detection level of the first run was a result of low-alititude haze. This message may be cited.