Neutron absorption correction and mean path length calculations for multiple samples with arbitrary shapes -- applications to highly absorbing samples on the Multi-Axis Crystal Spectrometer at NIST

TL;DR

This paper examines and expands a finite volume algorithm for neutron absorption correction, enabling accurate data correction and experiment planning for complex, arbitrarily shaped samples in neutron scattering measurements.

Contribution

The paper extends an existing algorithm to correct for absorption in multiple co-aligned samples with arbitrary shapes, improving accuracy in neutron scattering data analysis.

Findings

The expanded algorithm accurately accounts for angular-dependent absorption.

It effectively corrects neutron scattering data for complex sample geometries.

The method aids in experimental planning and data correction for highly absorbing samples.

Abstract

The finite volume algorithm for absorption correction developed by Wunch and Prewitt is examined. This algorithm is based on the numerical integration of the transmission function where three-dimensional quadratic surfaces define the sample boundaries. The algorithm can also calculate the mean path length required for second-extinction calculations. We apply this method to the neutron inelastic scattering measurements of CeRhIn$_{5}$ using the Multi-Axis Crystal Spectrometer (MACS) at NIST. The algorithm has been expanded to correct the absorption of multiple coaligned samples. We show that this procedure can account for the angular-dependent absorption, and the technique can be used to correct data and plan experiments.