{
  "bibcode": "2009GCN..8811....1E",
  "body": "P.A. Evans (U. Leicester)  and H. A. Krimm (CRESST/GSFC/USRA) report on behalf\nof the Swift-XRT team:\n\nWe have analysed 5.5 ks of XRT data for GRB 090113 (Krimm et al. GCN Circ.\n8804), beginning 93 s after the BAT trigger. The data are entirely in Photon\nCounting (PC) mode. The enhanced XRT position for this burst was given by Goad\net al. (GCN. Circ 8809).\n\nThe light curve can be modelled with a power-law decay with a decay index of\nalpha=0.991 (+/-0.042).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed power-law\nwith a photon spectral index of 2.28 (+0.20, -0.19). The best-fitting absorption\ncolumn is 3.20 (+0.63, -0.58) x 10^21, in excess of the Galactic value of 6.7 x\n10^20 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10\nkeV flux conversion factor deduced from this spectrum is 4.0 x 10^-11 (7.8 x\n10^-11) erg cm^-2 count^-1.\n\nIf the light curve continues to decay with a power-law decay index of 0.991, the\ncount rate at T+24 hours will be 0.0063 count s^-1, corresponding to an observed\n(unabsorbed) 0.3-10 keV flux of 2.5 x 10^-13 (4.9 x 10^-13) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00339852.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 8811,
  "createdOn": 1231918664000,
  "email": "pae9@star.le.ac.uk",
  "subject": "GRB 090113: Swift-XRT refined analysis",
  "submitter": "Phil Evans at U of Leicester  <pae9@star.le.ac.uk>",
  "eventId": "GRB 090113"
}