{
  "bibcode": "2012GCN.13488....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 long-duration unusual GRB 120716A\n(IPN detection and localization: Hurley at al., GCN 13487)\ntriggered Konus-Wind at T0=61507.357s UT (17:05:07.357)\n\nThe light curve started with a short (~0.9 s) pulse followed,\nafter ~170 s, by a double-peaked structure lasting for ~60 s.\nThe total duration of the burst is ~230 s.\n\nThis GRB is similar to GRB 041219A, GRB 050820A, and GRB 060124,\nwhich display a rather short precursor, a ~200 s long period\nof quiescence, and the main episode of emission. For this burst,\nthe precursor is relatively short and bright and the main part\nis shorter and dimmer.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB120716_T61507/\n\nAs observed by Konus-Wind:\n   - the precursor had a fluence of 1.4(-0.3,+1.0)x10-6 erg/cm2,\nand a 64-ms peak flux, measured from T0-0.064 s,\nof 3.3(-0.8,+2.7)x10-6 erg/cm2/s;\n   - the main part of the burst\nhad a fluence of 1.3(-0.3,+0.3)x10-5 erg/cm2,\nand a 256-ms peak flux, measured from T0+181.760 s,\nof 8.8(-0.15,+0.15)x10-7 erg/cm2/s\n(both in the 20 keV - 10 MeV energy range).\n\nThe 3-channel spectrum of the precursor (from T0-0.256 to T0+0.512 s)\ncan be modeled  (in the 20-1200 keV range) by a power law\nwith exponential cutoff model with alpha = -1.3 � 0.1\nand Ep = 380 � 50 keV (one-sigma errors are given for this fit).\n\nThe time-integrated spectrum of the main emission episode\n(measured from T0+172.288 to T0+213.248 s)\nis well fit in the 20 keV - 5 MeV range\nby a power law with exponential cutoff model, for which:\nalpha = -1.50 (-0.2, +0.2),\nand Ep = 190(-44, +110) keV,\nchi2 = 59.2/75 dof.\nFitting this spectrum with the GRB (Band) function yields\nthe following model parameters:\nthe low-energy photon index alpha = -1.5 (-0.2, +0.3),\nthe high energy photon index beta = -2.4 (<-2.0),\nthe peak energy Ep = 175(-73, +96) keV,\nchi2 = 58.2/74 dof.\n\nThe spectrum at the maximum count rate\n(measured from T0+180.480 to T0+188.672 s) is best fitted\nis best fit in the 20 keV - 5 MeV range\nby a power law with exponential cutoff model, for which:\nalpha = -1.1 (-0.3, +0.3),\nand Ep = 180(-37, +68) keV,\nchi2 = 66.5/75 dof.\n\n\nAll the quoted results are preliminary.\nAll the quoted errors are at the 90% confidence level.",
  "circularId": 13488,
  "createdOn": 1342606877000,
  "email": "fred@mail.ioffe.ru",
  "subject": "Konus-Wind observation of GRB 120716A",
  "submitter": "Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>",
  "eventId": "GRB 120716A"
}