{
  "bibcode": "2020GCN.28397....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, very bright GRB 200903E\n(AGILE detection: Ursi et al., GCN Circ. 28356;\nAstroSat CZTI detection: Gupta et al., GCN Circ. 28367;\nIPN triangulation: Hurley et al., GCN Circ. 28383)\ntriggered Konus-Wind at T0=9267.293 s UT (02:34:27.293).\n\nThe burst light curve shows a bright, multi-peaked structure\nwhich started at ~T0-114.6 s and had a total duration of ~268.4 s.\nThe emission is seen up to ~6 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB200903_T09267/\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 4.84(-0.24,+0.23)x10^-4 erg/cm2,\nand a 64-ms peak flux, measured from T0+20.464 s,\nof 5.12(-0.57,+0.57)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+98.816 s)\nis best fit in the 20 keV - 6 MeV range\nby the GRB (Band) model with the following parameters:\nthe low-energy photon index alpha = -1.23(-0.03,+0.03),\nthe high energy photon index beta = -2.30(-0.14,+0.10),\nthe peak energy Ep = 413(-30,+33) keV\n(chi2 = 100/74 dof).\n\nThe spectrum near the maximum count rate\n(measured from T0+17.152 to T0+22.272 s)\nis best fit in the 20 keV - 6 MeV range\nby the GRB (Band) model with the following parameters:\nthe low-energy photon index alpha = -1.04(-0.05,+0.06),\nthe high energy photon index beta = -2.37(-0.35,+0.20),\nthe peak energy Ep = 717(-95,+106) keV\n(chi2 = 74/71 dof).\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 28397,
  "createdOn": 1599600350000,
  "email": "ridnaia@mail.ioffe.ru",
  "subject": "Konus-Wind detection of GRB 200903E",
  "submitter": "Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>",
  "eventId": "GRB 200903E"
}