{
  "circularId": 1635,
  "subject": "GRB 021004: optical spectroscopy on Oct 11",
  "submitter": "Alberto Castro-Tirado at Inst.de Astro. de Andalucia  <ajct@iaa.es>",
  "editedOn": 1731923601715,
  "version": 2,
  "createdOn": 1034622758000,
  "editedBy": "Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>",
  "body": "A. J. Castro-Tirado, E. Pérez, J. Gorosabel (IAA-CSIC,\nGranada), J. M. Castro Cerón (ROA, San Fernando),\nM. Andersen (AIP, Potsdam), J. Hjorth (Univ. of Copenhagen),\nE. Rol, R. Wijers (Univ. of Amsterdam), A. Fruchter\n(STScI, Baltimore), S. Klose (TLS, Tautenburg),\nJ. Greiner (MPE, Garching) and E. Pian (OAT-INAF, Trieste)\non behalf of the GRACE Collaboration\n\nreport:\n\n\"We have obtained a 7200-s spectrum with the FORS1\nspectrograph at the ESO's 8.2-m VLT3 telescope at\nParanal on Oct 11.125-11.231 UT. The range is 3500-\n5700 A with a resolution of about 1 A/pix.\n\nWe confirm the detection of the Ly-alpha (1215.7 A)\nemission line plus the C IV (1548,2 A, 1550.8 A)\nabsorption line system at a redshift z = 2.327 (GCN\n1605). The Al II (1670 A) absorption line (GCN 1618)\nis detected as well at the same redshift.\n\nWe also detect another two absorption line systems at\nz = 2.297 and z = 2.321 on the basis of C IV (1548,2 A,\n1550.8 A) lines.  The latter system is also detected in\nSi IV (1393.8, 1402.8).  These two systems are consistent\nwith those reported by Salamanca et al. (GCN 1611) and\nSavaglio et al. (GCN 1633).\n\nThe flux of the Ly-alpha line (1.9e-16 erg/cm2/s/A) is\ncomparable with the one measured by Keck (GCN 1620),\ni.e. the Lyman-alpha flux is constant and we conclude that\narises from the GRB 021004 host galaxy, at z = 2.327.\"\n\n\nThis message may be cited.",
  "format": "text/plain",
  "bibcode": "2002GCN..1635....1C",
  "eventId": "GRB 021004",
  "email": "ajct@iaa.es"
}