In-situ Polarized 3 He-Based Neutron Polarization Analyzer for SNS Magnetism Reflectometer

Lee, WT
Tong, X
Pierce, J
Fleenor, M
Ismaili, A
Robertson, JL
Chen, WC
Gentile, TR
Hailemariam, A
Goyette, R
Parizzi, A
Lauter, V
Klose, F
Kaiser, H
Lavelle, C
Baxter, DV
Jones, GL
Wexler, J
McCollum, L

Open link

Publication date

September 2011

DOI

10.1088/1742-6596/251/1/012086

Publisher

IOP Publishing

ISSN

1742-6596

Journal

Journal of Physics Conference Series

Citation count (estimate)

Abstract

We report here the construction and neutron transmission test results of an in-situ polarized 3 He-based neutron polarization analyzer system for the Magnetism Reflectometer at the Spallation Neutron Source, Oak Ridge National Laboratory. The analyzer uses the Spin-Exchange Optical Pumping method to polarize the 3 He nuclei of a cell of 3 He gas. Polarized neutrons scattered from the sample are intercepted by the polarized 3 He gas which strongly absorbs neutrons in one spin-state while allowing most neutrons in the other spin-state to pass through. To maintain a stable analyzing efficiency during an experiment, the 3 He gas is continuously polarized in - situ on the instrument. Neutron transmission measurements showed that 73% 3 He polariz...