{
  "bibcode": "2016GCN.18974....1T",
  "body": "A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks, P. Oleynik,\nM. Ulanov, D. Svinkin, A. Lysenko, A. Kozlova and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe long-duration, extremely hard-spectrum GRB 160131A\n(Swift-BAT trigger #672236: Page & Barthelmy, GCN 18951;\nCummings  et al., GCN 18959)\ntriggered Konus-Wind at T0=30044.577 s UT (08:20:44.577).\n\nThe burst light curve shows a single, FRED-like pulse\nwith a total duration (80-1400 keV) of ~200 s.\nIn the softest KW energy band the emission can be traced up to ~300 s.\nThe emission is seen up to ~15 MeV.\n\nAs observed by Konus-Wind, the burst\nhad a fluence of 3.26(-0.32,+0.31)x10^-4 erg/cm2,\nand a 64-ms peak energy flux, measured from T0+2.704 s,\nof 2.23(-0.46,+0.46)x10^-5 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+162.048 s)\nis best fit in the 20 keV - 15 MeV range\nby the GRB (Band) model with the following parameters:\nthe low-energy photon index alpha = -0.97(-0.15,+0.24),\nthe high energy photon index beta = -1.56(-0.10,+0.07),\nthe peak energy Ep = 586(-259,+518) keV,\nchi2 = 98/97 dof.\n\nThe spectrum near the peak count rate\n(measured from T0+0.256 to T0+14.592 s)\nis best fit in the 20 keV - 15 MeV range\nby the GRB (Band) model with the following parameters:\nthe low-energy photon index alpha = -0.94(-0.18,+0.13),\nthe high energy photon index beta = -1.56(-0.56,+0.06),\nthe peak energy Ep = 1152(-438,+3060) keV,\nchi2 = 135/97 dof.\n\nAssuming the redshift z=0.972 (Malesani et al., GCN 18965;\nde Ugarte Postigo, Thoene & Sanchez-Ramirez, GCN 18966;\nXu, Xin & Wang, GCN 18969)\nand a standard cosmology model with H_0 = 70 km/s/Mpc,\nOmega_M = 0.27, and Omega_Lambda = 0.73,\nwe estimate the following rest-frame parameters:\nthe isotropic energy release E_iso is ~8.3x10^53 erg,\nthe peak luminosity L_iso is ~1.1x10^53 erg/s,\nand the rest-frame peak energy of the time-integrated spectrum,\nEp,i, is ~1150 keV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB160131_T30044/\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 18974,
  "createdOn": 1454427365000,
  "email": "tsvetkova@mail.ioffe.ru",
  "subject": "Konus-Wind observation of GRB 160131A",
  "submitter": "Anastasia Tsvetkova at Ioffe Institute  <tsvetkova@mail.ioffe.ru>",
  "eventId": "GRB 160131A"
}