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arXiv · 2605.28661

Spin Phase Continuous Modulation: A Method for the Measurement of Neutron Monochromaticity

Ryuto Fujitani·Masahiro Hino·Takashi Higuchi
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Abstract

We present spin phase continuous modulation (SPCM), a new method for characterization of neutron beam properties. By utilizing spin-precession modulation induced by two oscillating magnetic fields, the method enables precise determination of neutron velocity and monochromaticity. We derive a theoretical formulation of the SPCM signal and experimentally validate it using measurements with a monochromatized neutron beam, obtaining reasonable agreement between experiment and prediction. SPCM enables quantitative determination of neutron beam velocity and monochromaticity.

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Ryuto Fujitani, Masahiro Hino, Takashi Higuchi. 2026-05-27. Spin Phase Continuous Modulation: A Method for the Measurement of Neutron Monochromaticity. https://arxiv.org/abs/2605.28661

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