{
  "bibcode": "2012GCN.13009....1P",
  "body": "K.L. Page (U. Leicester), C. Pagani (U. Leicester), V. D'Elia (ASDC),\nA. Maselli  (INAF-IASFPA), V. Mangano (INAF-IASFPA), M.C. Stroh (PSU),\nD.N. Burrows (PSU), J.A. Kennea (PSU), A.P. Beardmore (U. Leicester)\nand G. Stratta report on behalf of the Swift-XRT team:\n\nWe have analysed 8.2 ks of XRT data for GRB 120305A (Stratta  et al.\nGCN Circ. 13004), from 69 s to 24.9 ks after the  BAT trigger. The data\ncomprise 85 s in Windowed Timing (WT) mode with the remainder in Photon\nCounting (PC) mode. The enhanced XRT position for this burst was given\nby Beardmore et al. (GCN. Circ 13008).\n\nThe light curve can be modelled with  a power-law decay with a decay\nindex of alpha=2.66 (+0.22, -0.19).\n\nA spectrum formed from the WT mode data can be fitted with an absorbed\npower-law with a photon spectral index\tof 1.94 (+0.21, -0.20). The\nbest-fitting absorption column is  4.7 (+1.1, -0.9) x 10^21 cm^-2, in\nexcess of the Galactic value of 1.1 x 10^21 cm^-2 (Kalberla et al.\n2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion\nfactor deduced from this spectrum  is 4.5 x 10^-11 (7.5 x 10^-11) erg\ncm^-2 count^-1. \n\nA summary of the WT-mode spectrum is thus:\nTotal column:\t     4.7 (+1.1, -0.9) x 10^21 cm^-2\nGalactic foreground: 1.1 x 10^21 cm^-2\nExcess significance: 6.4 sigma\nPhoton index:\t     1.94 (+0.21, -0.20)\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00516997.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 13009,
  "createdOn": 1331020986000,
  "email": "pae9@star.le.ac.uk",
  "subject": "GRB 120305A: Swift-XRT refined Analysis",
  "submitter": "Phil Evans at U of Leicester  <pae9@star.le.ac.uk>",
  "eventId": "GRB 120305A"
}