TITLE: GCN CIRCULAR NUMBER: 8705 SUBJECT: GRB 081222: Swift XRT refined analysis DATE: 08/12/22 16:14:12 GMT FROM: Dirk Grupe at PSU/Swift-XRT Dirk Grupe (PSU) reports on behalf of the Swift-XRT team: The XRT began observing the field of GRB 081222 (trigger=337914; Grupe et al., GCN Circ 8691) on 2008-December-22 at 04:54:51.7 UT, 51.8 seconds after the BAT trigger. The 0.3-10 keV X-ray light curve of the first five orbits displays a smooth light curve that can be fitted with an initial decay slope alpha1 = 0.90+/-0.02 with a break at 1420+/-100s followed by a steeper decay slope alpha2=1.20+/-0.02. The spectrum of the Windowed Timing data of the first orbit can be well fitted by an absorbed single power law model with a photon index Gamma = 2.01 +/- 0.20 and a column density NH=(4.61+/-0.80)e20 which is in excess of the Galactic column density in the direction of the burst of NH-gal=2.24e20 (Kalberla et al. 2005). The photon counting mode data of the first five orbits are consistent with this result. If the underlying power law decay of 1.2 continues as is, we predict an XRT count rate of 0.030 counts/s at T+24 hours or 1e-12 ergs/s/cm2 and at T+48 hours 0.015 counts/s or 5e-13 ergs/s/cm2. This circular is an official product of the Swift-XRT team. [GCN OPS NOTE(23dec08): Per author's request, the "081221" in the first line was changed to "081222".]