{
  "bibcode": "2017GCN.20584....1D",
  "body": "A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), L. Izzo (IAA-CSIC), \nC. Thoene (IAA-CSIC), D.A. Kann (IAA-CSIC, TLS), P. Pessev \n(GRANTECAN, IAC, ULL), A. Perez (GRANTECAN) report on \nbehalf of a larger collaboration:\n\nWe observed the afterglow of GRB 170202A (Racusin et al. \nGCN 20575) using OSIRIS at the 10.4m GTC telescope at the \nRoque de los Muchachos observatory (La Palma, Spain). The \nobservation started at 23:22 UT (4.91 hr after the burst) and \nincluded observations with grisms R1000B and R1000R covering\n the ranges 3700 - 7800 AA and 5100 - 9300 AA respectively.\n\nThe blue spectra shows a strong signal with multiple features being \nespecially significant Lyman-alpha (both in absorption and emission), \nthe full Ly-forest, NV, SII, SiII, SiII*, OI, CII, SiIV, CIV and AlII at a \ncommon redshift of 3.645, which we identify as the redshift of the \nGRB.",
  "circularId": 20584,
  "createdOn": 1486081335000,
  "email": "deugarte@iaa.es",
  "subject": "GRB 170202A: Redshift from OSIRIS/GTC",
  "submitter": "Antonio de Ugarte Postigo at IAA-CSIC  <deugarte@iaa.es>",
  "eventId": "GRB 170202A"
}