Methods to maximize detector count rates on small-angle neutron scattering diffractometers at reactor sources: I. Optimizing wavelength selection

Published

April 1, 2024

Author(s)

John Barker, Jeremy Cook

Abstract

Methods to determine the optimal neutron wavelength to maximize detector count rates on small angle neutron scattering (SANS) diffractometers at reactor sources is presented. Three experimental methods are used to determine the choice of optimal wavelength and collimation combination that maximizes the detector count rate. The wavelength optimization methods are applied to two different SANS diffractometers at the NCNR, and all methods are found to confirm the optimal wavelength of approximately 9.5  0.5 Å for optically thin samples. The optimum wavelength is shifted by the wavelength-dependence of the sample transmission to 8.5  0.5 Å for thicker absorbing samples. The same optimization methods can be applied to SANS diffractometers at other reactor facilities.

Citation

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

Volume

1061

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.nima.2024.169107

Local Download

Keywords

Neutron scattering, small-angle scattering, pinhole collimation, wavelength optimization, instrument resolution, nuclear reactor

Citation

Barker, J. and Cook, J. (2024), Methods to maximize detector count rates on small-angle neutron scattering diffractometers at reactor sources: I. Optimizing wavelength selection, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, [online], https://doi.org/10.1016/j.nima.2024.169107, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=956310 (Accessed October 6, 2025)