{
  "bibcode": "2017GCN.22284....1S",
  "body": "D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, P. Oleynik,\nM. Ulanov, A. Tsvetkova, A. Lysenko, A.Kozlova, and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe long-duration, hard-spectrum GRB 171216B\n(IPN triangulation: Hurley et al., GCN circ. 22263;\nCALET-CGBM detection: Pal'shin et al., GCN circ. 22268)\ntriggered Konus-Wind at T0=51948.499 s UT (14:25:48.499).\n\nThe burst light curve shows a multipeaked structure\nwhich starts at ~T0-0.3 s and has a total duration of ~7.4 s.\nThe emission is seen up to ~5 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB171216_T51948/\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 1.59(-0.29,+0.37)x10^-5 erg/cm2,\nand a 16-ms peak flux, measured from T0+0.034 s,\nof 2.32(-1.00,+1.15)x10^-5 erg/cm2/s\n(both in the 20 keV - 10 MeV energy range).\n\nThe time-averaged spectrum of the burst\n(measured from T0 to T0+8.448 s)\nis best fit in the 20 keV - 10 MeV range\nby a power law with exponential cutoff model:\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith  alpha = -1.11(-0.11,+0.13)\nand Ep = 1341(-412,+673) keV (chi2 = 85/98 dof).\nFitting by a GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index: beta < -2.3\n(chi2 = 85/97 dof).\n\nThe spectrum near the maximum count rate\n(measured from T0 to T0+0.064 s)\nis best fit in the 20 keV - 10 MeV range\nby a power law with exponential cutoff model:\nwith  alpha = -0.34(-0.37,+0.52)\nand Ep = 994(-372,+539) keV (chi2 = 15/16 dof).\nFitting by a GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index: beta < -2.2\n(chi2 = 15/15 dof).\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 22284,
  "createdOn": 1514216262000,
  "email": "svinkin@mail.ioffe.ru",
  "subject": "Konus-Wind observation of GRB 171216B",
  "submitter": "Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>",
  "eventId": "GRB 171216B"
}