Applications of 3He neutron spin filters at the NCNR

Core-Shell Magnetic Morphology of Structurally Uniform Magnetite Nanoparticles

“…With the neutron polarization spin state as þ or À, measurement of all four neutron spin cross-sections ( þ þ, þ À , À þ , and À À ) allows for the unique separation of nuclear scattering (N 2 ) from magnetic scattering, irrespective of whether the sample is magnetically saturated. Application of polarization analysis to SANS [17][18][19] has been very limited since it requires a polarization analyzer capable of capturing a divergent, 2D, scattered beam, such as a polarized 3 He spin filter [20]. Additionally, we expand beyond the formalism of previous work [18] to directly measure the magnetic structure from moments oriented perpendicular to the applied field (…”

In-situ compact3He neutron spin polarizer based on a magneto-static cavity with built-in NMR coils

“…Unlike neutron guides or neutron benders, which change the neutron beam alignment and/or neutron spatial beam uniformity owing to their characteristic multiple reflections, polarized 3 He neutron polarizers are free from such beam misalignment and beam interference [1]. In addition, a 3 He polarizer has a wide acceptance angle and creates a smaller amount of background gamma radiation owing to its low neutron activation [2].…”

“…In addition, a 3 He polarizer has a wide acceptance angle and creates a smaller amount of background gamma radiation owing to its low neutron activation [2]. Such merits enable the 3 He polarizer to be widely used for neutron experiments in fundamental particle physics or material researches involving neutron radiography, neutron diffraction, neutron reflectometry, neutron interferometry, and small-angle neutron scattering [3,4].…”

“…At KAERI, two programs were recently funded to develop a 3 He polarizer and a polarizing supermirror for a deployment of polarized neutrons in the neutron beam lines of the HANARO (Highflux Advanced Neutron Application ReactOr). A neutron guide test station G-TS will be utilized to test both types of polarizers.…”

“…Currently, one of the top priorities is to apply the developed neutron polarizers for a neutron reflectometer (REF-V). In addition, the 3 He polarizer will be deployed for He polarizers based on a compact solenoid coil or a compact magneto-static cavity. In this paper, we report a 3 He-cell fabrication station and a magneto-static cavity based 3 He polarizer.…”