TITLE: GCN CIRCULAR NUMBER: 6796 SUBJECT: GRB 070917: Swift-XRT observations DATE: 07/09/18 08:53:44 GMT FROM: Phil Evans at U of Leicester P.A. Evans, A.P. Beardmore, K.L. Page, R.L.C. Starling (U. Leicester) and J.R. Cummings (NASA/UMBC) report on behalf of the Swift-XRT team: We have analysed 2.3 ks of Swift XRT data for GRB 070917 (Cummings et al. GCN Circ 6791) beginning 35 ks after the trigger. The data are entirely in Photon Counting mode. An uncatalogued X-ray source is clearly detected at RA, Dec= 293.91913, +2.41055 degrees, which is equivalent to: RA (J2000) = 19h 35m 40.59s Dec(J2000) = +02d 24' 38.0" with an estimated uncertainty of 8.0 arcsec (radius, 90% containment including boresight uncertainty). This is 37 arcsec from the BAT refined position (Tueller et al. GCN Circ 6792). The source has a count rate of 0.016 counts s^-1. At present we are unable to determine whether the source is fading, however observations are ongoing. Using the C-statistic in xspec we fit the PC mode spectrum from T0+35000-42000 s with an absorbed power-law. The absorption is consistant with the Galactic value of 1.73e21 cm^-2 (Kalberla et al. 2005). The spectral slope is gamma=1.17 (+0.44/-0.45), which is consistent with the BAT value of 1.52 +/- 0.04. The observed (unabsorbed) flux is 1.31e-12 (1.44e-12) erg/cm^2/s. This circular is an official product of the Swift team.