{
  "bibcode": "2020GCN.27398....1R",
  "body": "A. Ridnaia, S. Golenetskii, R. Aptekar, D. Frederiks,\nM. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe long-duration GRB 200311A\n(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 27363;\nAGILE-MCAL detection: Ursi et al., GCN Circ. 27365;\nAstroSat-CZTI detection: Gupta et al., GCN Circ. 27371;\nIPN triangulation: Svinkin et al., GCN Circ. 27381)\ntriggered Konus-Wind at T0=54974.737 s UT (15:16:14.737).\n\nThe burst light curve shows a multipeaked structure\nwhich starts at ~T0-0.8 s and has a total duration of ~65.2 s.\nThe emission is seen up to ~8 MeV.\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 8.84(-0.76,+0.89)x10^-5 erg/cm2,\nand a 64-ms peak flux, measured from T0+1.792 s,\nof 1.56(-0.28,+0.28)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+64.512 s)\nis best fit in the 20 keV - 8 MeV range\nby a power law with exponential cutoff model:\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith  alpha = -0.93(-0.07,+0.08)\nand Ep = 854(-112,+142) keV (chi2 = 113/81 dof).\nFitting by a GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index: beta < -2.1\n(chi2 = 112/80 dof).\n\nThe spectrum near the maximum count rate\n(measured from T0+0.256 to T0+7.168 s)\nis best fit in the 20 keV - 8 MeV range\nby a power law with exponential cutoff model\nwith  alpha = -0.57(-0.08,+0.09)\nand Ep = 957(-98,+114) keV (chi2 = 88/80 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 = 86/79 dof).\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB200311_T54974/\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 27398,
  "createdOn": 1584445897000,
  "email": "ridnaia@mail.ioffe.ru",
  "subject": "Konus-Wind observation of GRB 200311A",
  "submitter": "Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>",
  "eventId": "GRB 200311A"
}