{
  "bibcode": "2005GCN..4022....1K",
  "body": "J. A. Kennea, D. N. Burrows (PSU), M. Goad (U. Leicester), J. Norris and\nN. Gehrels (GSFC) report on behalf of the Swift/XRT Team:\n\nWe report on detailed ground analysis of the first 2 orbits of data from\nX-ray afterglow of GRB050922C (GCN 4013) utilizing downlinked Swift/XRT\ndata.  We find a refined position for the XRT afterglow of:\n\nRA(J2000):  21:09:33.3,\nDec(J2000): -8:45:27.5,\n\nwith an estimated uncertainty of 6 arcseconds radius (90% containment). We note \nthat this position is 4.6 arcseconds from the NOT optical afterglow position \nreported in GCN 4015.\n\nWe have extracted a lightcurve of combined Window Timing and Photon \nCounting mode data from the first two orbits of XRT observations, covering \n6500ks of time.  The lightcurve of the afterglow is well described by a \nsingle powerlaw model with a slope of -1.14 +/- 0.02.\n\nThe spectrum of the afterglow is well fit (reduced Chi^2 = 0.94 with 44 dof) by \nan absorbed power-law model with the following parameters:\n\nN_H = (6.5 +/- 2.7) x 10^20 cm^-2\nPhoton Index = 1.89 +/- 0.16\n\nThe absorption seen here is consistant with the expected Galactic absorption of \n5.75 x 10^20 cm^-2. Utilizing this spectral model, we estimate the flux of this \nburst (corrected for absorption) to be:\n\nBAT Trigger +1 hour: 1.5 x 10^-11 erg/s/cm^2 (0.5 - 10 keV)\nBAT Trigger +1 day:  3.9 x 10^-13 erg/s/cm^2 (0.5 - 10 keV)\n\nNote that the latter flux estimate assumes that the lightcurve does not\nbreak.\n\nObservations of this burst by Swift are on-going.",
  "circularId": 4022,
  "createdOn": 1127444263000,
  "email": "kennea@astro.psu.edu",
  "subject": "GRB 050922C: Swift XRT refined analysis",
  "submitter": "Jamie A. Kennea at PSU/Swift-XRT  <kennea@astro.psu.edu>",
  "eventId": "GRB 050922C"
}