{
  "bibcode": "2009GCN..9553....1G",
  "body": "S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,\nP. Oleynik, M. Ulanov, and D. Svinkin on behalf of\nthe Konus-Wind and Konus-RF teams, and\nT. Cline on behalf of the Konus-Wind team, report:\n\nThe long GRB 090618 (Schady et al. 2009, GCN 9512)\ntriggered Konus-Wind\nat T0=30504.974 s UT (08:28:24.974),\nand Konus-RF instrument onboard CORONAS-PHOTON s/c\nat T0=30507.060 s UT (08:28:27.060).\n\nThe burst light curve shows a smooth multi-peaked structure\nwith a duration of ~160 s. Significant spectral evolution\nwas observed during the burst.\n\n-- \nAs observed by Konus-Wind the burst had\na fluence of (2.5 � 0.06)x10-4 erg/cm2,\nand a 64-ms peak flux measured from T0+63.616 s\nof (1.6 � 0.2)x10-5 erg/cm2/s\n(both in the 20 keV - 2 MeV energy range).\n\nThe time-integrated spectrum of the burst\n(from T0 to T0+142 s) can be fitted\n(in the 20 keV - 2 MeV range) by GRB (Band) model\nfor which:\nthe low-energy photon index alpha = -1.28 � 0.02,\nthe high energy photon index beta = -2.66(-0.2, +0.14),\nthe peak energy Ep = 186 � 8 keV (chi2 = 103/60 dof).\n\nThe spectrum at the maximum count rate,\nmeasured from T0+62.720 to T0+64.0 s, is well fitted\n(in the 20 keV - 2 MeV range) by GRB (Band) model\nfor which:\nthe low-energy photon index alpha = -0.99 (-0.06, +0.07),\nthe high energy photon index beta = -2.29(-0.5, +0.23),\nthe peak energy Ep = 440 � 70 keV (chi2 = 52/55 dof).\n\n-- \nAs observed by Konus-RF the burst\nhad a fluence of (2.82 � 0.06)x10-4 erg/cm2\n(both in the 20 keV - 2 MeV energy range),\nand a 500-ms peak flux measured from T0+63.0 s\nof (1.6 � 0.1)x10-5 erg/cm2/s\n(in the 20 keV - 1.5 MeV energy range).\n\nThe time-integrated spectrum of the burst\n(from T0-1.4 to T0+113.0 s) can be fitted\n(in the 20 keV - 2 MeV range) by GRB (Band) model\nfor which:\nthe low-energy photon index alpha = -1.28 � 0.03,\nthe high energy photon index beta = -3.06(-0.5, +0.3),\nthe peak energy Ep = 220 � 8 keV (chi2 = 240/132 dof).\n\nThe spectrum at the maximum count rate,\nmeasured from T0+63.0 to T0+63.5 s, is well fitted\n(in the 20 keV - 1.5 MeV range) by GRB (Band) model\nfor which:\nthe low-energy photon index alpha = -0.89 (-0.1, +0.3),\nthe high energy photon index beta = -2.56(-1.0, +0.6),\nthe peak energy Ep = 385 (-136, +64) keV (chi2 = 78/74 dof).\n\n-- \nAll the quoted values are preliminary.\nThe quoted errors are at the 90% confidence level.\n\nThe light curves of this GRB is available\nat http://www.ioffe.ru/LEA/GRBs/GRB090618_T30504/",
  "circularId": 9553,
  "createdOn": 1245681705000,
  "email": "fred@mail.ioffe.ru",
  "subject": "Konus-Wind and Konus-RF observations of GRB 090618",
  "submitter": "Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>",
  "eventId": "GRB 090618"
}