GCN Circular 4992
M.R. Goad, K.L. Page (U Leicester) and D.N. Burrows (PSU) report on behalf of the Swift-XRT team: We have analysed the first 14 ks of Photon Counting (PC) mode data, starting 97 seconds after the BAT trigger time, determining a refined position of RA (J2000): 22 54 32.63 Dec(J2000): +62 43 50.07 with an estimated uncertainty of 3.8 arcsec (90% containment). This is 1.7 arcsec from the initial XRT position given by Goad & Page in GCN 4987 and 16.2 arcsec from the on-board BAT position quoted in GCN 4985 (Goad et al.) The X-ray source was initially quite faint, with a peak count rate of only ~1 count s^-1. The light-curve shows a flat decay of alpha = 0.49 +/- 0.29, breaking to a steeper slope of alpha = 1.54 +/- 0.36, approximately 1500 seconds after the burst. Because of the faintness of the afterglow, only 3 seconds of data were obtained in Windowed Timing mode before switching into PC. The first orbit of PC data (97-717 seconds post-trigger) can be modelled with a simple power-law of Gamma = 1.54 +/- 0.34, with the Galactic absorbing column of 1e22 cm^-2. The observed (unabsorbed) flux over 0.3-10 keV for this time period is 3.78e-11 (5.64e-11) erg cm^-2 s^-1. Assuming the current rate of decay continues, the estimated count rate at 24 hours is 4.2e-3 count s^-1, corresponding to an observed (unabsorbed) flux of 4.55e-14 (6.38e-14) erg cm^-2 s^-1. This circular is an official product of the Swift-XRT team.