Analysis of X‐ray spectra by iterative least squares (AXIL): New developments

TLDR

The paper discusses recent changes to AXIL and their application to accurate micro‑XRF image evaluation. The authors introduced an orthogonal‑polynomial background model, extended the Gaussian photopeak model to capture non‑Gaussian peak components, and added PC‑MCA card control and looped command execution to improve AXIL’s usability. These extensions improve AXIL’s spectrum evaluation performance, enhancing accuracy for energy‑dispersive X‑ray spectra.

Abstract

Abstract The functionality of the computer package AXIL (Analysis of X‐ray spectra by Iterative Least squares), suitable for the evaluation of energy‐dispersive X‐ray spectra, has been extended in a number of ways. First, a background modelling algorithm, based on the use of mutually orthogonal polynomials was introduced to replace the linear or exponential polynomials employed previously. Second, the Gaussian photopeak model employed in previous versions of the program was extended to include the non‐Gaussian parts of the characteristic peaks and related background contributions. Both innovations are shown to improve the performance of the spectrum evaluation procedure. Third, the user‐friendliness of the evaluation program was enhanced (a) by allowing a PC plug‐in MCA card to be directly controlled from within the program and (b) by extending the command‐interface to allow for repeated execution of series of commands by means of control loops. A brief description of these changes is given; as an application, the accurate evaluation of micro‐XRF images is discussed.