{
  "bibcode": "2000GCN...851....1C",
  "body": "Sandra M. Castro, S. G. Djorgovski, S. R. Kulkarni, J. S. Bloom, T. J. Galama,\nF. A. Harrison (Caltech), and D. A. Frail (NRAO), report on behalf of a\nlarge collaboration:\n\nWe analysed high-resolution spectra of the optical afterglow of GRB 000926\nkindly obtained at the WMKO Keck-II telescope by L. Cowie, A. Barger, et al.\non UT 2000 September 29.26, using the ESI instrument (an Echelle spectrograph).\n\nOur preliminary analysis yields a single absorption system including the \nfollowing lines: Si II 1526.7, C IV 1548.2 and 1550.5, Al II 1670.8, Si II\n1808.0, Al III 1854.7 and 1862.8, Zn II 2026.1, Fe II 2344.2, 2373.7, 2382.8,\n2586.6, and 2600.2, Mg II 2796.3 and 2803.5, and Mg I 2853.0.  The mean\nredshift is z = 2.0369 +- 0.0007, presumably corresponding to the system\nidentified by Fynbo et al. (GCN 807) as having z ~ 2.066.  However, we see \nno evidence for any other absorption systems in these data; in particular, \nthe ostensible system at z = 1.378 proposed by Fynbo et al. is likely due to\nline misidentifications.\n\nWe note that the line equivalent widths appear to be unusually strong in\ncomparison to the general population of metallic line absorbers seen in the\nspectra of quasars, suggesting a high column density and/or metallicity of\nthe intervening gas.  A more detailed analysis is in progress.\n\nThis note can be cited.",
  "circularId": 851,
  "createdOn": 971567935000,
  "email": "george@oracle.caltech.edu",
  "subject": "GRB 000926:  Improved Absorber Redshift",
  "submitter": "George Djorgovski at Caltech/Palomar  <george@oracle.caltech.edu>",
  "eventId": "GRB 000926"
}