{
  "bibcode": "2008GCN..8004....1B",
  "body": "A.P. Beardmore (U. Leicester) and M. Stamatikos (NASA/ORAU)\nreport on behalf of the Swift-XRT team :\n\nWe have analysed the first two orbits of Swift-XRT data obtained\nfrom GRB 080723A (trigger 317662;  Stamatikos et al., GCN Circ. 8000).\nThe data were taken in photon counting mode and have an exposure of\n2.83 ks,  spanning 88 s to 7.44 ks after the trigger. The UVOT-enhanced\nXRT position was given by Beardmore et al. in GCN Circ. 8001.\n\nThe light curve can be modelled by a doubly broken power-law, with\nan inital decay of alpha1 = 1.77 +0.34 -0.25 which flattens to a shallow\ndecay of alpha2 = 0.05 +/- 0.24 at a time tbreak1 = 365 +68 -46 s. This is\nfollowed by a further steepening to  alpha3 = 1.39 +/- 0.75 at a time\ntbreak2 = 3.4 +1.2 -1.8 ks.\n\nThe spectrum of the photon counting mode data from the first two orbits\ncan be fit with an absorbed power-law to give a photon index gamma =\n2.39 +0.30 -0.28 and NH = (7.7 +2.5 -2.2)e21 cm^-2, in addition to the\nGalactic column of 3.9e+21 cm^-2 in the direction of the GRB. The observed\n0.3-10 keV flux is  (1.14 +0.10 -0.22)e-11 erg cm^-2 s^-1, which corresponds\nto an unabsorbed flux of 3.57e-11 erg cm^-2 s^-1.\n\nIf the light curve continues to decay at the same rate we estimate the count\nrate will be 3.2e-2 count/s  one day after the trigger, which corresponds to\nan observed  flux of 1.9e-13 erg cm^-2 s^-1.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 8004,
  "createdOn": 1216827327000,
  "email": "apb@star.le.ac.uk",
  "subject": "GRB 080723A: Swift-XRT refined analysis",
  "submitter": "Andy Beardmore at U Leicester  <apb@star.le.ac.uk>",
  "eventId": "GRB 080723A"
}