TITLE: GCN CIRCULAR NUMBER: 11693 SUBJECT: GRB 110210A: Swift-XRT refined Analysis DATE: 11/02/10 20:12:41 GMT FROM: Valerio D'Elia at ASDC G. Stratta, V. D'Elia (ASDC) report on behalf of the Swift-XRT team: We have analysed 5.6 ks of XRT data for GRB 110210A (D'Elia et al. GCN Circ. 11687), from 126 s to 19.3 ks after the BAT trigger. The data comprise 226 s in Windowed Timing (WT) mode (the first 9 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN. Circ 11689). After an initial fading behavior, the light curve is consistent with a constant source of mean count rate 4.5e-01 ct/sec. A power-law fit gives an index of 0.0 (+/-0.3). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 3.10 (+0.09, -0.08). The best-fitting absorption column is 2.16 (+0.17, -0.16) x 10^21 cm^-2, in excess of the Galactic value of 5.3 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode spectrum has a photon index of 2.16 (+0.15, -0.19) and a best-fitting absorption column of 7.5 (+4.5, -1.9) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.6 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 7.5 (+4.5, -1.9) x 10^20 cm^-2 Galactic foreground: 5.3 x 10^20 cm^-2 Excess significance: 6.4 sigma Photon index: 2.16 (+0.15, -0.19) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00445141. This circular is an official product of the Swift-XRT team. [GCN OPS NOTE(10feb11): Per author's request, the fourth sentence was replaced. Acknowledgement to H.Kann.]