Monte Carlo simulation of Nb Kα secondary fluorescence in EPMA: comparison of PENELOPE simulations with experimental results

Abstract

Secondary fluorescence across phase boundaries is a difficult problem encountered in several electron probe microanalysis (EPMA) situations: diffusion couples; small phases enclosed in a larger phases; eutectic intergrowths; and thin films. In some cases, it is possible to construct nondiffused couples and to measure the amount of secondary fluorescence across the phase boundary, but in most cases this is difficult, time consuming, expensive, or impossible. It is thus desirable to model the secondary fluorescence by Monte Carlo methods. Here we compare the results of experimentally measured secondary fluorescence of Nb K a with results from the PENELOPE Monte Carlo program, and find that there is close correspondence.

Constraining atmospheric oxygen and seawater sulfate concentrations during Paleoproterozoic glaciation: In situ sulfur three-isotope microanalysis of pyrite from the Turee Creek Group, Western Australia

“…10), similar to that observed in the $2.7 Ga Jeerinah Fm and $2.5 Ga Mount McRae Shale in Western Australia (Ono et al, 2003) as well as the $2.5 Ga Klein Naute Fm in South Africa (Ono et al, 2009). Pyrite with positive d 34 S and large, positive D 33 S likely received its sulfur from atmospheric S 8 , whereas pyrite with negative D 33 S and large, (Fournelle et al, 2005). Scale bars are 10 lm.…”

Bremsstrahlung enhancement in electron probe microanalysis for homogeneous samples using Monte Carlo simulation

“…Nowadays, all the quantification routines are based on these models, some of which have been developed under the assumption that bremsstrahlung fluorescence correction is negligible when compared to characteristic enhancement; however, no concluding arguments have been provided in order to support this assumption. Monte Carlo simulations constitute a very important tool for estimating the fluorescence enhancement, and a number of specific situations have already been faced with this approach (Fisher, ; Llovet et al ., ; Fournelle et al ., ; Tylko, ).…”

Monte Carlo Simulation of Characteristic Secondary Fluorescence in Electron Probe Microanalysis of Homogeneous Samples Using the Splitting Technique

“…Despite there exist many approaches available for the assessment of fluorescence enhancement (Reed, 1965; Ugarte et al, 1987), it is impossible to compare these predictions with experimental data as the photons produced by fluoresced atoms cannot be discriminated from the total recorded radiation. Therefore, Monte Carlo simulations constitute a very important tool for estimating the fluorescence enhancement and a number of specific situations have been faced with this approach (Fisher, 1971; Hu & Pan, 2001; Llovet & Galan, 2003; Fournelle et al, 2005; Fournelle, 2007).…”