{
  "bibcode": "2013GCN.14356....1G",
  "body": "S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin,\nP. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf\nof the Konus-Wind team, report:\n\nThe very long intense GRB 130320B\n(IPN triangulation: Hurley et al., GCN 14354)\ntriggered Konus-Wind at T0=48251.726s UT (13:24:11.726)\n\nThe burst consists of three emission episodes with a total duration of ~380 s.\nThe first episode (from ~T0-1 to ~T0+15s) shows very bright\nmulti-peaked pulse with strong hard-to-soft spectral evolution.\nThe second episode is a single weak soft-spectrum pulse\nfrom T0+135 to T0+175s. The third episode (from ~T0+195 to ~T0+380s)\nalso shows a single pulse, more intense and harder than the second one.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB130320_T48251/\n\nAs observed by Konus-Wind, the burst\nhad a total fluence of (7.8 � 0.3)x10-5 erg/cm2,\nand a 64-ms peak flux, measured from T0+0.704s,\nof (7.2 � 1.8)x10-6 erg/cm2/s\n(both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum (measured from T0 to T0+384.768 s)\nis best fit in the 20 keV - 15 MeV range\nby a simple power law with the photon index 2.24 � 0.03,\nchi2 = 85.5/98 dof.\n\nThe spectrum at the onset of the burst (measured from T0 to T0+0.256 s)\nis best fit in the 20 keV - 15 MeV range\nby the GRB (Band) function with the following model parameters:\nthe low-energy photon index alpha = -1.0 � 0.3,\nthe high energy photon index beta = -2.0 � 0.3,\nthe peak energy Ep = 340 � 190 keV,\nchi2 = 23/25 dof.\n\nThe average spectrum of the second emission episode\n(measured from T0+139.008 to T0+188.160 s)\nis best fit in the 20 keV - 2 MeV range\nby a power law with exponential cutoff model,\nfor which:\nalpha = -1.7 � 0.3,\nand Ep = 46 � 23 keV,\nchi2 = 47/58 dof.\n\nThe average spectrum of the third emission episode\n(measured from T0+294.656 to T0+384.768 s)\nis best fit in the 20 keV - 15 MeV range\nby the GRB (Band) function with the following model parameters:\nthe low-energy photon index alpha = -1.23 � 0.17,\nthe high energy photon index beta = -2.25 � 0.19,\nthe peak energy Ep = 156 � 29 keV,\nchi2 = 91.6/96 dof.\n\n\nAll the quoted results are preliminary.",
  "circularId": 14356,
  "createdOn": 1364644748000,
  "email": "fred@mail.ioffe.ru",
  "subject": "Konus-Wind observation of GRB 130320B",
  "submitter": "Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>",
  "eventId": "GRB 130320B"
}