Beardmore, A. P.A. P.BeardmoreGodet, O.O.GodetAbbey, A. F.A. F.Abbey2020-09-172020-09-172006-05-01https://hdl.handle.net/20.500.13025/483GAMMA-RAY BURSTS IN THE SWIFT ERA Sixteenth Maryland Astrophysics Conference. AIP Conference Proceedings, Volume 836, pp. 708-711 (2006).The Swift X-ray Telescope (XRT) focal plane camera houses a front-illuminated MOS CCD, providing a spectral response of 145 eV FWHM at 5.9 keV. We describe the status of the CCD X-ray spectral redistribution matrices, which are made using a Monte-Carlo simulation technique based on physical models of the CCD response. We emphasize how the model has been refined following in-flight experience with celestial and on-board calibration sources. Residuals less than 10% are typically observed for astrophysical sources.10.1063/1.2207983http://adsabs.harvard.edu/abs/2006AIPC..836..708B2006AIPC..836..708B