A set of universal curves can be used to estimate the scattered x-ray spectrum from an arbitrary thickness of water and a monoenergetic primary exit spectrum. By approximating the primary exit spectrum as a discrete spectrum of narrow energy bins (photons per keV vs keV), these curves allow for a rapid estimation (±20%) of the resultant scatter spectrum. Experimental confirmation is shown.
William E. Moore,
"A Method For Estimating X-Ray Scatter Spectra", Proc. SPIE 0419, Application of Optical Instrumentation in Medicine XI, (13 December 1983); doi: 10.1117/12.936008; https://doi.org/10.1117/12.936008