{
  "bibcode": "2017GCN.22039....1M",
  "body": "D. Malesani (DARK/NBI), J. P. U. Fynbo (NBI), K. E. Heintz (Univ. \nIceland and DARK/NBI), M. Stone (Turku Univ.), K. Karhunen (Turku \nUniv.), report on behalf of a larger collaboration:\n\nFollowing our imaging sequence (Malesani et al., GCN 22029), we secured \nspectra of the optical afterglow of GRB 171020A (Page et al., GCN \n22028), using the AlFOSC spectrograph at the Nordic Optical Telescope. A \ntotal of 4x1200 s exposure was secured using grism #4, covering the \nwavelength range ~3600-9400 AA. Spectroscopy started on 2017 Oct 21.005 \nUT (1 hr after the trigger).\n\nA faint trace is detected down to at least ~4000 A. Several weak \nabsorption features are detected, which we interpret as due to Mg II, Fe \nII, and C IV all at a common redshift z = 1.87.\n\nWe thank the NOT staff for support, in particular Amanda Djupvik and \nSergio Armas.",
  "circularId": 22039,
  "createdOn": 1508604205000,
  "email": "malesani@dark-cosmology.dk",
  "subject": "GRB 171020A: NOT spectroscopic redshift",
  "submitter": "Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>",
  "eventId": "GRB 171020A"
}