{
  "bibcode": "2019GCN.24730....1S",
  "body": "D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks,\nM. Ulanov, A. Tsvetkova, A. Lysenko, A. Kozlova, and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe long-duration GRB 190531B\n(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 24695;\nFermi-GBM observations: Veres and Meegan, GCN Circ. 24705;\nFermi-LAT detection: Axelsson et al., GCN Circ. 24701;\nInsight-HXMT/HE detection: Yi et al., GCN Circ. 24713)\ntriggered Konus-Wind at T0=72616.175 s UT (20:10:16.175).\n\nThe burst light curve shows a multipeaked structure\nwhich starts at ~T0-38 s and has a total duration of ~110 s.\nThe emission is seen up to ~5 MeV.\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 1.51(-0.15,+0.16)x10^-4 erg/cm2,\nand a 64-ms peak flux, measured from T0+17.648 s,\nof 1.96(-0.30,+0.30)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+83.712 s)\nis best fit in the 20 keV - 5 MeV range\nby the GRB (Band) model with the following parameters:\nthe low-energy photon index alpha = -0.73(-0.08,+0.08),\nthe high energy photon index beta = -2.25(-0.21,+0.14),\nthe peak energy Ep = 364(-34,+40) keV\n(chi2 = 63/72 dof).\n\nThe spectrum near the maximum count rate\n(measured from T0+15.616 to T0+19.456 s)\nis best fit in the 20 keV - 7 MeV range\nby the GRB (Band) model with the following parameters:\nthe low-energy photon index alpha = -0.60(-0.08,+0.09),\nthe high energy photon index beta = -2.64(-0.46,+0.26),\nthe peak energy Ep = 520(-53,+55) keV\n(chi2 = 87/77 dof).\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB190531_T72616/\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 24730,
  "createdOn": 1559584344000,
  "email": "svinkin@mail.ioffe.ru",
  "subject": "Konus-Wind observation of GRB 190531B",
  "submitter": "Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>",
  "eventId": "GRB 190531B"
}