{
  "bibcode": "2019GCN.24652....1T",
  "body": "A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks,\nM. Ulanov, D. Svinkin, A. Lysenko, A. Kozlova and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe long-duration GRB 190519A\n(Fermi GBM observation: Fermi GBM team, GCN 24594; von Kienlin, GCN 24596;\nSwift detection: Ukwatta et al., GCN 24595; Lien et al., GCN 24606;\nCALET Gamma-Ray Burst Monitor detection: Yamaoka et al., GCN 24611;\nAstroSat CZTI detection: Ghumatkar et al., GCN 24613)\ntriggered Konus-Wind at T0=26732.082 s UT (07:25:32.082).\n\nThe burst light curve shows two pulses.\nThe first one starts at T0-39.0 s and ends at T0-3.7 s.\nThe second, bright, double-peaked pulse starts at T0-3.7 s and ends at \nT0+11.6 s.\nThe total duration of the burst is ~51 s.\nThe emission is seen up to ~1.5 MeV.\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 3.20(-0.16,+0.18)x10^-5 erg/cm2,\nand a 64-ms peak energy flux, measured from T0+6.752 s,\nof 5.80(-1.01,+1.01)x10^-6 erg/cm2/s\n(both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum of the main pulse\n(measured from T0 to T0+15.616 s)\nis best fit in the 20 keV - 1.5 MeV range\nby a power law with exponential cutoff model:\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith�� alpha = -1.05(-0.09,+0.10),\nand Ep = 125(-6,+7) keV (chi2 = 67/60 dof).\nFitting by the GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index:\nbeta < -3.05 (chi2 = 67/59 dof).\n\nThe spectrum near the peak count rate\n(measured from T0+0.256 to T0+7.424 s)\nis best fit in the 20 keV - 1.5 MeV range\nby the power law with exponential cutoff model\nwith�� alpha = -0.93(-0.10,+0.10),\nand Ep = 136(-6,+7) keV (chi2 = 65/60 dof).\nFitting by the GRB (Band) model yields the same alpha and Ep,\nand an upper limit on the high energy photon index:\nbeta < -2.96 (chi2 = 64/59 dof).\n\nModeling the K-W 3-channel spectrum of the initial pulse\n(measured from T0-38.980 s to T0-3.652 s)\nby a simple power law yields the photon index of 2.21(-0.07,+0.08),\nchi2 = 0.94/1 dof.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB190519_T26732/\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 24652,
  "createdOn": 1558529655000,
  "email": "tsvetkova@mail.ioffe.ru",
  "subject": "Konus-Wind observation of GRB 190519A",
  "submitter": "Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>",
  "eventId": "GRB 190519A"
}