{
  "bibcode": "2006GCN..5209....1B",
  "body": "A.P. Beardmore, O. Godet (U. Leicester) and T. Sakamoto  (GSFC/ORAU) \nreport on behalf of the Swift-XRT team :\n\nWe have analysed the first 11.4ks of Swift XRT PC mode data from the BAT\ntrigger GRB060602B (Schady et al., GCN 5200; trigger number 213190). We \nfind a refined XRT position of:\n\nRA(J2000)  =  17:49:31.6\nDec(J2000) = -28:08:03.2\n\nwith an estimated uncertainty of 3.7 arcsec (90% containment). This is\n1.4 arcsec away from the XRT position reported in GCN 5200 and 64.2 \narcsec from the refined BAT position (Palmer et al., GCN 5208).\n\nThe X-ray light curve shows a small rise in intensity until T+200s, then \nfollows a simple power-law decay with a index of 1.05 +/- 0.07.\n\nThe X-ray spectrum over the same interval (T+100s to T+40ks) can be well \nmodelled by an absorbed power-law, with a photon index of 3.1 +/- 0.6 \nand a column density of 5.0 +/- 1.4 E22 cm^-2. The measured galactic \ncolumn density in this direction is 1.4E22 cm^-2. The observed 0.3-10keV \nflux is 3.2E-12 ergs cm**-2 s**-1, which corresponds to an unabsorbed \nflux of 5.0E-11 ergs cm**-2 s**-1. The measured spectral and temporal \nindices are difficult to reconcile with standard GRB afterglow models.\n\nThe X-ray spectrum can also be equally well fit by an absorbed blackbody \nmodel, with a temperature of 0.90+/-0.09 keV and a column density of 2.1 \n+/- 0.7 E22 cm^-2. This model has an observed (unabsorbed) 0.3-10 keV flux \nof 2.8E-12 (4.3E-12) ergs cm**-2 s**-1.\n\nAssuming the source decays at the same rate, we predict an XRT count \nrate of 0.0011 count/s at T+48 hrs, which corresponds to an  observed \nflux of 8.8E-14 ergs cm**-2 s**-1.\n\nThis Circular is an official product of the Swift XRT Team.",
  "circularId": 5209,
  "createdOn": 1149381218000,
  "email": "apb@star.le.ac.uk",
  "subject": "GRB 060602B: Swift-XRT Refined Analysis",
  "submitter": "Andy Beardmore at U Leicester  <apb@star.le.ac.uk>",
  "eventId": "GRB 060602B"
}