{
  "bibcode": "2012GCN.12959....1S",
  "body": "M.C. Stroh (PSU), D.N. Burrows (PSU), P.A. Evans (U. Leicester), O.M.\nLittlejohns (U. Leicester), J.P. Osborne (U. Leicester), B. Sbarufatti\n(INAF-OAB/PSU), G. Stratta (ASDC), P. D'Avanzo (INAF-OAB), J.A. Kennea\n(PSU) and E.A. Hoversten report on behalf of the Swift-XRT team:\n\nWe have analysed 9.4 ks of XRT data for GRB 120215A (Hoversten\tet al.\nGCN Circ. 12954), from 110 s to 19.3 ks after the  BAT trigger. The\ndata comprise 36 s in Windowed Timing (WT) mode with the remainder in\nPhoton Counting (PC) mode. The enhanced XRT position for this burst was\ngiven by Evans et al. (GCN. Circ 12957).\n\nThe light curve can be modelled with an initial power-law decay with an\nindex of alpha=3.38 (+0.26, -0.23), followed by a break at T+699 s to\nan alpha of -0.28 (+0.15, -0.18).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 2.10 (+0.24, -0.22). The\nbest-fitting absorption column is  8.4 (+5.1, -3.0) x 10^20 cm^-2,\nconsistent with the Galactic value of 5.4 x 10^20 cm^-2 (Kalberla et\nal. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux\nconversion factor deduced from this spectrum  is 3.4 x 10^-11 (4.4 x\n10^-11) erg cm^-2 count^-1. \n\nA summary of the PC-mode spectrum is thus:\nTotal column:\t     8.4 (+5.1, -3.0) x 10^20 cm^-2\nGalactic foreground: 5.4 x 10^20 cm^-2\nExcess significance: <1.6 sigma\nPhoton index:\t     2.10 (+0.24, -0.22)\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00515015.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 12959,
  "createdOn": 1329310263000,
  "email": "pae9@star.le.ac.uk",
  "subject": "GRB 120215A: Swift-XRT refined Analysis",
  "submitter": "Phil Evans at U of Leicester  <pae9@star.le.ac.uk>",
  "eventId": "GRB 120215A"
}