Correcting Aberrations of a Transverse-Field Neutron Resonance Spin Echo Instrument

TL;DR

This paper presents a novel static-field correction magnet for neutron resonance spin echo instruments, effectively reducing aberrations and improving polarization, validated through simulations and neutron experiments.

Contribution

It introduces a new static-field magnet design that corrects transverse-field NRSE aberrations, enhancing instrument performance.

Findings

Simulation shows effective aberration correction

Experimental results confirm improved polarization

Prototype design is feasible and effective

Abstract

The neutron resonance spin echo (NRSE) technique has the potential to increase the Fourier time and energy resolution in neutron scattering by using radio-frequency (rf) neutron spin-flippers. However, aberrations arising from variations in the neutron path length between the rf flippers reduce the polarization. Here, we develop and test a transverse static-field magnet, a series of which are placed between the rf flippers, to correct for these aberrations. The prototype correction magnet was both simulated in an NRSE beamline using McStas, a Monte Carlo neutron ray-tracing software package, and measured using neutrons. The results from the prototype demonstrate that this static-field design corrects for transverse-field NRSE aberrations.