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arXiv · 2209.11635

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

Stephen J. Kuhn·Sam McKay·Fankang Li·Robert M. Dalgliesh·Eric Dees·Kaleb Burrage·Jiazhou Shen·Roger Pynn
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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.

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Stephen J. Kuhn, Sam McKay, Fankang Li, Robert M. Dalgliesh, Eric Dees, Kaleb Burrage, Jiazhou Shen, Roger Pynn. 2022-09-23. Correcting Aberrations of a Transverse-Field Neutron Resonance Spin Echo Instrument. https://doi.org/10.1063/5.0128097

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