{
  "bibcode": "2010GCN.11474....1G",
  "body": "J.M. Gelbord (PSU) and D. Grupe (PSU) report on behalf of the\nSwift-XRT team:\n\nWe have analysed 5.8 ks of XRT data for GRB 101219A (Gelbord et al.\nGCN Circ. 11461), from 70 s to 18.0 ks after the  BAT trigger. The\ndata comprise 13 s in Windowed Timing (WT) mode with the remainder in\nPhoton Counting (PC) mode.\n\nThe light curve after 200s can be modelled as a power-law decay. The\ndecay index is alpha=-1.8 (+/-0.2).\n\nA spectrum formed from the PC mode data can be fitted with an absorbed\npower-law with a photon spectral index of 1.78 (+0.25, -0.23). The\nbest-fitting absorption column is 3.1 (+1.1, -0.9) x 10^21 cm^-2,\nin excess of the Galactic value of 4.87 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 4.9 x 10^-11 (6.9 x 10^-11) erg\ncm^-2 count^-1.\n\nA summary of the PC-mode spectrum is thus:\nTotal column:        3.1 (+1.1, -0.9) x 10^21 cm^-2\nGalactic foreground: 4.9 x 10^20 cm^-2\nExcess significance: 4.8 sigma\nPhoton index:        1.78 (+0.25, -0.23)\n\nIf the light curve continues to decay with a power-law decay index of\n1.8, the count rate at T+24 hours will be 2 x 10^-5 count s^-1,\ncorresponding to an observed (unabsorbed) 0.3-10 keV flux of 7.5 x\n10^-16 (1.1 x 10^-15) erg cm^-2 s^-1.\n\nThe results of the XRT-team automatic analysis are available at\nhttp://www.swift.ac.uk/xrt_products/00440606.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 11474,
  "createdOn": 1292793008000,
  "email": "jgelbord@astro.psu.edu",
  "subject": "GRB 101219A: Swift-XRT refined Analysis",
  "submitter": "Jonathan Gelbord at PSU/Swift  <jgelbord@astro.psu.edu>",
  "eventId": "GRB 101219A"
}