TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4031 SUBJECT: GRB050922B: refined XRT analysis DATE: 05/09/23 16:39:11 GMT FROM: Olivier Godet at U.of Leicester O. Godet, K.L. Page, J. Kennea (PSU), J.P. Osborne (U. Leicester), D. N. Burrows (PSU), N. Gehrels (NASA/GSFC), K. Hurley (Berkeley), M. Chester (PSU) report on behalf of the Swift XRT team: We have analyzed the Swift XRT data of the burst GRB 050922B from the first 3 orbits (~4 ks). The refined coordinates are: RA(J2000) = 00h 23min 13.2s Dec(J2000) = -05d 36' 16.4" with an uncertainty of 7 arcseconds radius (90% containment). This position is consistent with that reported by Norris et al. (GCN 4008). Initial data show two flares peaking at ~370 s and ~846 s after the trigger (T0), followed by a steep temporal decline decay (power law decline index ~ 2.75+/-0.14). Later data from the second and third orbits show a shallow decline with an temporal index ~ 0.95 +/- 0.41. The X-ray spectrum after T0+5021 s is well fit by a power-law with Gamma = 1.9+0.3/-0.2 (90% confidence) and a Galactic absorbing column of 3.4e20 cm^-2. If the light-curve is still unbroken at T0+24 h, the predicted unabsorbed 0.3-10 keV flux is ~1.6e-13 erg cm^-2 s^-1. [GCN OPS NOTE(23sep05): Per author's request, J. Kennea as was added to the author list.]