TITLE: GCN CIRCULAR NUMBER: 5758 SUBJECT: GRB061025: Swift XRT refined analysis DATE: 06/10/26 15:07:08 GMT FROM: Vanessa Mangano at INAF-IASFPA T. Mineo (IASF-Pa), V. Mangano (IASF-Pa), G. Cusumano (IASF-Pa), and B. Sbarufatti (IASF-Pa) report on behalf of the Swift XRT team: We analysed the first 9 ks of Swift-XRT data obtained in PC mode for GRB061025 detected by INTEGRAL (Mereghetti et al. 2006, GCN 5751). The light-curve shows a first shallow decay (alpha1=0.7+/-0.8) up to a break at t_break=20+/-4 ks, followed by a steeper decay (alpha2=3.4+/-1.2). If decaying at the present rate the source will reach a level of 1E-4 c/s at 24 hr since the trigger. The average spectrum can be modelled with a power-law of photon index Gamma = 1.7 ± 0.4, with an absorbing column consistent with the Galactic value of 5E20 cm-2. The average unabsorbed flux is (4.3 ±0.8)E-13 ergs cm-2 s-1, corresponding to a count rate of 5.3E-3 c/s. All errors are quoted at 90% confidence level. This circular is an official product of the Swift-XRT team.