{
  "bibcode": "2013GCN.15144....1C",
  "body": "A. Cucchiara (UCSC/UCO Lick Observatory), D. Perley (Caltech) \nreport on behalf of a larger collaboration:\n\n\"We observed the afterglow of GRB 130831A (Hagen et al. \nGCN 15139, Guidorzi et al. GCN 15140) with the GMOS spectrograph \non Gemini-North, beginning approximately 50 min after the BAT trigger.\n\nWe obtained 2x900s exposure spectra under exquisite conditions \nusing the B600 grism, covering the 3860-6649 Angstrom wavelength range.\n\nIn our preliminary analysis we detect MgII2796,2803 doublet and \nMgI2853 absorption lines at z=0.4791.\n\nNo other strong features are detected in absorption or in emission, \ntherefore we suggest this as the redshift of GRB 130831A.\n\n\nWe thank the Gemini-N staff, in particular Adam Smith and \nAnthony Matulonis, for their support.\"",
  "circularId": 15144,
  "createdOn": 1377963452000,
  "email": "acucchia@ucolick.org",
  "subject": "GRB 130831A: Gemini-North Redshift",
  "submitter": "Antonino Cucchiara at UCSC/UCO Lick  <acucchia@ucolick.org>",
  "eventId": "GRB 130831A"
}