GCN Circular 14635
P.A. Evans (U. Leicester) and F. E. Marshall (NASA/GSFC) report on behalf of the Swift-XRT team: We have analysed 3.9 ks of XRT data for the INTEGRAL-detected burst: GRB 130513A (Mereghetti et al., GCN 14630), from 25.4 ks to 37.2 ks after the INTEGRAL trigger. The data are entirely in Photon Counting (PC) mode. An X-ray source is detected within the INTEGRAL error circle. Using 2486 s of PC mode data and 2 UVOT images, we find an enhanced XRT position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 144.76167, -5.24171 which is equivalent to: RA (J2000): 09h 39m 02.80s Dec(J2000): -05d 14' 30.1" with an uncertainty of 2.7 arcsec (radius, 90% confidence). This position is 49 arcsec from the INTEGRAL position. The source is fading, and the light curve can be modelled with a power-law of index 3.3 (+1.1, -0.45). We therefore conclude that it is the afterglow of the GRB. We detect only 24 photons from this source, so the spectrum is poorly constrained. The photon index is 2.9 (+2.1, -1.1); the absorption is consistent with the Galactic value of 3.4e20 cm^-2 (Kalberla et al. 2005) however within the errors on the spectral fit, could be as high as 5e21 cm^-2. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00020274. This circular is an official product of the Swift-XRT team.