Simulating neutron diffraction from deformed mosaic crystals in McStas

TL;DR

This paper introduces a new simulation component for neutron diffraction from bent mosaic crystals in McStas, validated against other software and analytical calculations, enhancing neutron scattering modeling capabilities.

Contribution

A novel McStas component for simulating neutron diffraction from bent mosaic crystals, validated against existing software and analytical models.

Findings

Excellent agreement with SIMRES and Ncrystal simulations.

Validation against analytical Darwin transfer equations.

Enhanced modeling of neutron diffraction in bent crystals.

Abstract

Monochromator and analyzer systems that rely on bent single crystals are in use throughout the neutron scattering community. We here introduce a new component to the neutron simulation software package McStas, that simulates these bent single crystals. We then compare the performance of this component to like software in SIMRES, and Ncrystal. These simulations show excellent agreement across the different software programs. Finally we compare simulations of the new McStas component with analytical calculations of secondary extinction, based on the Darwin transfer equations. Here we also find excellent agreement, further validating this new component.