TITLE: GCN CIRCULAR NUMBER: 974 SUBJECT: GRB010222: Another absorption line system DATE: 01/02/23 05:14:40 GMT FROM: Saurabh Jha at Harvard-Smithsonian CfA S. Jha, T. Matheson, M. Calkins, M. A. Pahre, K. Z. Stanek, J. McDowell, R. Kilgard (Harvard-Smithsonian CfA), and P. M. Garnavich (Notre Dame) report: Further reduction and analysis of the FLWO 1.5m spectrum of the GRB 010222 optical afterglow (GCN 965) reveals the presence of two absorption systems along the line of sight to the gamma-ray burst, one at z = 1.477 as reported, and another with weaker lines at z = 1.157. The interstellar absorption lines observed from each system are as follows, with identifications based on the ultraviolet spectral atlas of Blades et al. (1988, ApJ, 334, 308): Observed Line Rest Redshift Wavelength Identification Wavelength (A) (A) 7065.4 Mg I 2852.1 1.477 6941.7 Mg II 2802.7 1.477 6924.0 Mg II 2795.5 1.477 6438.5 Fe II 2599.4 1.477 6422.4 Mn II 2593.7 1.476 6405.4 Fe II 2585.9 1.477 6381.2 Mn II 2576.1 1.477 5900.1 Fe II 2382.0 1.477 5879.6 Fe II 2373.7 1.477 5805.4 Fe II 2343.5 1.477 5108.5 Zn II/Cr II blend 2061.9 1.478 5018.5 Zn II/Mg I blend 2025.6 1.478 4478.9 Si II 1808.0 1.477 4137.8 Al II 1670.8 1.477 3838.0 C IV blend 1549.0 1.478 3781.8 Si II 1526.7 1.477 6045.0 Mg II 2802.7 1.157 6028.2 Mg II 2795.5 1.156 5606.7 Fe II 2599.4 1.157 5574.1 Fe II 2585.9 1.156 5137.2 Fe II 2382.0 1.157 This message can be cited.