Treatment of EXAFS data taken in the fluorescence mode in non-linear conditions

Abstract The aim of this work is to investigate the possibility of extracting correct structural parameters from fluorescence EXAFS data taken at high count rates with an energy-resolving detector. This situation is often encountered on third generation synchrotron radiation sources which provide a high flux on the sample. We have quantified in a real experiment the errors caused by pulse pile-up in the extraction of structural information and have elaborated different approaches to the problem of data correction. We discuss the different approaches by comparing the ability of each kind of correction to recover the correct structural parameters. The result of our analysis is that it is possible to work in non-linear conditions and correct the data, providing the response function of the acquisition system is known. Reliable structural information can be obtained with data acquired up to a count rate equal to approximately 60% of the inverse of the dead time.