{
  "bibcode": "2010GCN.10444....1R",
  "body": "A. Rowlinson (U Leicester) reports on behalf of the Swift-XRT team:\n\nWe have analysed 3.8 ks of XRT data for GRB 100219A (Rowlinson et al.\nGCN Circ. 10430), from 207 s to 28.4 ks after the BAT trigger. The data\nare entirely in Photon Counting (PC) mode. The enhanced XRT position for\nthis burst was given by Evans et al. (GCN. Circ 10437).\n\nThe light curve can be modelled with an initial power-law decay with an\nindex of alpha=1.53 (+0.28, -0.22), followed by a break at T+785 s to an\nalpha of 0.57 (+/-0.06).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.72 (+0.16, -0.13). The\nbest-fitting absorption column is 8.8 (+4.2, -0.0) x 10^20 cm^-2, in\nexcess of the Galactic value of 6.5 x 10^20 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 (5.3 x 10^-11) erg\ncm^-2 count^-1.\n\nIf the light curve continues to decay with a power-law decay index of\n0.57, the count rate at T+24 hours will be 0.035 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.6 x\n10^-12 (1.8 x 10^-12) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00412982.\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 10444,
  "createdOn": 1266649876000,
  "email": "bar7@star.le.ac.uk",
  "subject": "GRB 100219A: XRT refined analysis",
  "submitter": "Antonia Rowlinson at U.of Leicester  <bar7@star.le.ac.uk>",
  "eventId": "GRB 100219A"
}