TITLE: GCN CIRCULAR NUMBER: 11778 SUBJECT: GRB 110305A: Swift-XRT refined Analysis DATE: 11/03/06 16:43:19 GMT FROM: Dirk Grupe at PSU/Swift-XRT D. Grupe (PSU) reports on behalf of the Swift-XRT team: We have analyzed 34 ks of XRT data for GRB 110305A (Grupe et al. GCN Circ. 11773), from 116 s to 99.9 ks after the BAT trigger. The data are entirely in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 11777). The light curve can be modeled with a single power-law decay with a decay index of alpha=1.12 (+0.07, -0.06). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.98 (+0.22, -0.20). The best-fitting absorption column is consistent with the Galactic value of 1.7 x 10^21 cm^-2 (Kalberla et al. 2005). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.9 x 10^-11 (6.8 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.7 x 10^21 cm^-2 Galactic foreground: 1.7 x 10^21 cm^-2 Excess significance: Photon index: 1.98 (+0.22, -0.20) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00448229. This circular is an official product of the Swift-XRT team.