{
  "bibcode": "2022GCN.32783....1R",
  "body": "A.Ridnaia, D. Frederiks, A.Lysenko, D. Svinkin,\nA. Tsvetkova,  M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nThe long-duration GRB 221016A\n(Fermi-GBM detection: Fermi GBM team, GCN#32773,\nBissaldi et al., GCN#32782;\nSwift-BAT detection: Page et al., GCN#32774)\ntriggered Konus-Wind at T0=85166.713 s UT (23:39:26.713).\n\nThe burst light curve shows a single emission pulse\nwhich starts at ~T0-1.7 s and has a total duration of ~12.5 s.\nThe emission is seen up to ~2 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB221016_T85166/\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 5.46(-0.74,+1.07)x10^-6 erg/cm2,\nand a 64-ms peak flux, measured from T0+0.800 s,\nof 1.87(-0.73,+0.74)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+16.640 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 = -1.02(-0.33,+0.40)\nand Ep = 207(-46,+98) keV (chi2 = 60/99 dof).\nFitting by a GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index: beta < -2.0\n(chi2 = 60/98 dof).\n\nThe spectrum near the maximum count rate\n(measured from T0+0.256 to T0+8.448 s)\nis best fit in the 20 keV - 10 MeV range\nby a power law with exponential cutoff model\nwith  alpha = -0.89(-0.30,+0.35)\nand Ep = 166(-26,+39) keV (chi2 = 81/96 dof).\nFitting by a GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index: beta < -2.4\n(chi2 = 81/95 dof).\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 32783,
  "createdOn": 1666015578000,
  "email": "ridnaia@mail.ioffe.ru",
  "subject": "Konus-Wind detection of GRB 221016A",
  "submitter": "Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>",
  "eventId": "GRB 221016A"
}