Method for the Analysis of Multicomponent Exponential Decay Curves

Abstract

A frequently encountered problem in many branches of science involves the resolution of experimental data into a sum of independent exponential curves of the form f(t)= ∑ i=1nNiexp(−λit),in order to estimate the physically significant parameters Ni and λi. Such problems arise, for example, in the analysis of multicomponent radioactive decay curves, and in the study of the dielectric properties of certain compounds. This paper is concerned with the numerical evaluation of a mathematical approach to the problem. The approach is based on the inversion of the Laplace integral equation by a method of Fourier transforms. The results of the analysis appear in the form of a frequency spectrum. Each true peak in the spectrum indicates a component, the abscissa value at the center of the peak is the decay constant λi, while the height of the peak is directly proportional to Ni/λi. Results obtained on an IBM 650 computer indicate that the method may possess certain advantages over previous methods of analysis.