{
  "bibcode": "2017GCN.21036....1T",
  "body": "A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks, P. Oleynik,\nM. Ulanov, D. Svinkin, A. Lysenko, A. Kozlova and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe long-duration GRB 170424A\n(Fermi-LAT detection: Omodei & Vianello, GCN 21032;\nFermi GBM detection: Stanbro, von Kienlin & Meegan, GCN 21033)\ntriggered Konus-Wind at T0=36769.094 s UT (10:12:49.094).\n\nThe burst light curve shows a single pulse  which started\nat ~T0-20 s and lasted until ~T0+42 s (the total duration is ~62 s).\nThe emission is seen up to ~5 MeV.\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 3.46(-0.32,+0.44)x10^-5 erg/cm2,\nand a 64-ms peak energy flux, measured from T0-0.046 s,\nof 2.81(-1.05,+1.11)x10^-6 erg/cm2/s\n(both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum of the burst\n(measured from T0 to T0+41.216 s)\nis best fit in the 20 keV - 18 MeV range\nby a power law with exponential cutoff model:\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith  alpha = -0.91(-0.19,+0.23),\nand Ep = 353(-70,+111) keV (chi2 = 82/98 dof).\nFitting by the GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index:\nbeta < -2.01 (chi2 = 82/97 dof).\n\nThe spectrum near the peak count rate\n(measured from T0 to T0+8.448 s)\nis best fit in the 20 keV - 18 MeV range\nby the GRB (Band) model with the following parameters:\nthe low-energy photon index alpha = -0.77(-0.23,+0.33),\nthe high energy photon index beta = -3.30(-6.70,+1.17),\nthe peak energy Ep = 446(-127,+170) keV,\nchi2 = 108/97 dof.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB170424_T36769/\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 21036,
  "createdOn": 1493141611000,
  "email": "tsvetkova@mail.ioffe.ru",
  "subject": "Konus-Wind observation of GRB 170424A",
  "submitter": "Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>",
  "eventId": "GRB 170424A"
}