Proton hyperpolarization for polarized neutron scattering

水素核超偏極技術を用いた中性子構造解析手法の開発

熊田 高之   

Kumada, Takayuki

スピンコントラスト変調法は、中性子の水素核に対する散乱能が互いのスピンの向きに強く依存する性質を用いて複合材料の構造解析を行う手法である。我々は2009年以来、スピンコントラスト変調中性子小角散乱実験を展開しているほか、最近ではスピンコントラスト変調法を中性子反射率測定にも展開させたほか、結晶構造解析にも展開しようと計画している。

Scattering length of thermal and cold neutrons for protons remarkably depends on relative direction of their spins. Thus, scattering pattern of polarized neutrons varies as a function of proton-polarization of target samples. Spin-contrast-variation (SCV) is a technique to determine detailed structural information of composite materials from the polarization-dependent multiple scattering curves. We started the SCV-SANS measurements in 2009 in Japan Research Reactor (JRR-3) and Japan Proton Accelerator Research Complex (J-PARC), and carried out a lot of measurements. Recently, we succeed in determining multiple surface and interface structure parameters of multi-layered systems using SCV neutron reflectometry. We are also developing SCV neutron powder diffractometry, which determines crystalline structure by distinguishing overlapped multiple peaks from the polarization-dependent peak patterns.