{
  "bibcode": "2017GCN.22204....1D",
  "body": "A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), L. Izzo (HETH/IAA-CSIC),\nD.A. Kann (HETH/IAA-CSIC), C.C. Thoene (HETH/IAA-CSIC), P. Pesev (GTC),\nR. Scarpa (GTC), D. Perez (GTC) report on behalf of a larger collaboration:\n\nWe have been monitoring the counterpart of GRB 171205A (D'Elia et al. \nGCN22177; Izzo et al., GCN 22180) photometrically and spectroscopically \nwith OSIRIS at the 10.4m GTC telescope. Our latest observation consisted of \n3x600s exposure using the R1000B grism, which covers the spectral range \nbetween 3700 and 7880 Angstrom. On the combined spectrum, with epoch on \nthe 7th of December at 6:05 UT, we detect broad undulating spectral features, \nwhich are prominent between 4000 and 6000 Angstrom, superposed to the \nafterglow continuum, which seem to indicate the emergence of an underlying \nsupernova component. The features include a double bump in this range, \nsimilar to what was seen for the very early spectra of SN 1998bw (Patat et al. \n2001), indicating that this is probably also a broad line Ic supernova.\n\nFurther information will be provided through the TNS.",
  "circularId": 22204,
  "createdOn": 1512670438000,
  "email": "deugarte@iaa.es",
  "subject": "GRB 171205A: Detection of the emerging SN",
  "submitter": "Antonio de Ugarte Postigo at IAA-CSIC  <deugarte@iaa.es>",
  "eventId": "GRB 171205A"
}