TITLE: GCN CIRCULAR NUMBER: 7208 SUBJECT: GRB 080123: Swift-XRT refined analysis DATE: 08/01/23 17:24:42 GMT FROM: Boris Sbarufatti at INAF-IASF-Pa V. Mangano, B. Sbarufatti (INAF-IASF PA), T. N. Ukwatta (GSFC/GWU), and D. N. Burrows (PSU) report on behalf of the Swift XRT team: We have analyzed the XRT data collected during the first three orbits of observation of GRB 080123 (Ukwatta et al., GCN Circ. 7203). We have 124 s of exposure in WT mode (from T+108 to T+224 s) and 7.1 ks in PC mode. The initial XRT on-board position was centered on a cosmic ray hit. This position was retracted. The XRT position reported in GCN Circ. 7203 was obtained from the first downlinked data, but we note that the error circle given in this circular erroneously ignored the systematic component and was therefore much too small. The new, refined position of the XRT afterglow is 22h 35m 46.6s, -64d 54' 03.8" (J2000) with an error circle radius of 3.9" (90% confidence). As reported by Osborne et al. (GCN Circ. 7204), the UVOT-enhanced astrometric position is RA, Dec = 338.94226, -64.90090 which is equivalent to: RA (J2000): 22h 35m 46.1s Dec (J2000): -64d 54' 03.24" with an uncertainty of 2.1 arcsec (radius, 90% confidence). The X-ray light curve of the source shows a doubly broken power law behaviour, with an initial decay with slope 1.7 +/- 0.2, a first break at T+203 +/- 10 s, a second decay phase with slope 6.9 +/- 0.4, a second break at T+436 +/- 250 s and a third decay phase with slope 1.2 +/- 0.3. If decaying at this rate the source will be at the level of 9.0e-5 counts/s at T+24 hr. The WT spectrum is well fitted by an absorbed power law with photon index 1.64 +/- 0.09, while the PC spectrum can be fitted by a power law with photon index of 2.1 +/- 0.2. Both spectra are consistent with an absorption column of (8.1 +/- 2.4)e20 cm^-2, in excess with respect to the Galactic absorption along the line of sight (2e20 cm^-2, Kalberla et al. 2005). The observed (unabsorbed) flux in the 0.3-10 keV band is 7.0e-10 (7.9e-10) erg cm^-2 s^-1 for the WT spectrum and 1.1e-12 (1.4e-12) erg cm^-2 s^-1 for the PC spectrum. This circular is an official product of the Swift-XRT team.