Re-evaluation of Neutron-4He Elastic Scattering Data near 20 MeV

TL;DR

This paper re-evaluates neutron-4He elastic scattering data near 20 MeV, correcting previous overestimations of multiple scattering effects using advanced Monte Carlo techniques, leading to more accurate cross sections.

Contribution

It provides a revised analysis of neutron-4He scattering data with improved correction methods, enhancing the accuracy of the reported cross sections.

Findings

Earlier corrections overestimated multiple scattering effects by tenfold.

Revised differential cross sections are provided with improved accuracy.

Legendre coefficients are updated based on the corrected data.

Abstract

Measured differential elastic scattering cross sections of 17.71-, 20.97-, and 23.72-MeV neutrons from liquid helium-4 were re-evaluated and corrected for sample size and multiple scattering effects by means of a Monte Carlo technique implemented in a more recent code (MCNPX). Results indicate that earlier corrections via a code, MAGGIE-2, overestimated the size of multiple scattering effects by an order of magnitude. The corrected differential cross sections and Legendre coefficients obtained by least-squares fits are given.