Spectral noise removal by new digital smoothing routine

Smoothing is an indispensable process in X-ray photoelectron and Auger spectrometry, being used to reduce high-frequency noise, to obtain first derivatives and to suppress spurious oscillations in deconvoluted spectra. This paper reports the main properties of smoothing filters and proposes a new smoothing routine based on the binomial filter. This routine, in an automatic way, adapts the smoothing action of the binomial filter to the statistical quality of the spectra. In this way it is possible to reduce the noise without losing spectral resolution. Some examples of this application are given.