A method to determine the absolute harmonic content of an X-ray beam using attenuation measurements

We present a new method for determining the absolute harmonic content of an X-ray beam. The technique is applied to determine the harmonic content of a synchrotron beam to high-accuracy by measuring the X-ray attenuation of a large number of aluminium foils with thicknesses varying over several orders of magnitude. Earlier methods always determined relative quantities such as the effective harmonic content, which are dependant on experimental geometry and not transferable between detectors. We use a more fundamental and useful parameter: the harmonic-photon percentage. Copyright © 2009 John Wiley & Sons, Ltd.