{
  "bibcode": "2010GCN.10752....1C",
  "body": "S. B. Cenko, D. A. Perley, A. N. Morgan, C. R. Klein, J. S. Bloom, N. R.\nButler, and B. E. Cobb (UC Berkeley) report on behalf of a larger\ncollaboration:\n\nWe have obtained an optical spectrum of the afterglow (Morgan et al., GCN\n10747) of GRB 100513A (Baumgartner et al., GCN 10746) with the Gemini\nMulti-Object Spectrograph mounted on the 8 m Gemini North\ntelescope.  Observations began at 6:13 UT on 13 May (~ 4.1 hours after the\nGRB) and cover the wavelength range from 6000-10000 A.\n\nThe spectrum exhibits a strong break at approximately 7000 A which we\nassociate with a damped Ly-alpha system at z ~ 4.8.  We identify a series\nof narrow absorption features redward of Ly-alpha, including O I 1302, Si\nII 1304, C II 1334, C II* 1335, Si IV 1393, 1402, Si II 1526, and C IV\n1548, 1550 all at a common redshift of z = 4.772.  The presence of C II*,\nalong with Ly-alpha forest continuum emission blueward of 7000 A, strongly\nsuggest this is the redshift of the GRB host galaxy.\n\nThe presence of the Ly-alpha break at 7000 A further explains the\nrelatively faint R-band afterglow observed by Perley et al (GCN 10750;\nalso Updike et al., GCN 10748).\n\nWe wish to thank the entire Gemini staff, in particular Richard McDermid,\nfor the prompt execution of these observations.",
  "circularId": 10752,
  "createdOn": 1273736393000,
  "email": "cenko@srl.caltech.edu",
  "subject": "GRB 100513A: Gemini/GMOS Spectroscopic Redshift",
  "submitter": "S. Bradley Cenko at Caltech  <cenko@srl.caltech.edu>",
  "eventId": "GRB 100513A"
}