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arXiv · 2207.08441

Study of Thin Iron Films for Polarization Analysis of Ultracold Neutrons

Hiroaki Akatsuka·Takashi Higuchi·Sean Hansen-Romu·Kichiji Hatanaka·Tomohiro Hayamizu·Masahiro Hino·Go Ichikawa·Sohei Imajo·Blair Jamieson·Shinsuke Kawasaki·Masaaki Kitaguchi·Ryohei Matsumiya·Kenji Mishima
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Abstract

The TUCAN (TRIUMF Ultra-Cold Advanced Neutron) collaboration aims to search for the neutron electric dipole moment (nEDM) with unprecedented precision. One of the essential elements for the nEDM measurement is a polarization analyzer of ultracold neutrons (UCNs), whose main component is a magnetized thin iron film. Several thin iron films were deposited on aluminum and silicon ubstrates and were characterized by vibrating sample magnetometry and cold-neutron reflectometry. A magnetic field required to saturate the iron film is $\sim$12 kA/m for those on the aluminum substrates and 6.4 kA/m for the silicon substrates. The magnetic potential of the iron films on the Si substrate was estimated to be 2 T by the neutron reflectometry, which is sufficient performance for an UCN polarization analyzer of the nEDM measurement.

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Hiroaki Akatsuka, Takashi Higuchi, Sean Hansen-Romu, Kichiji Hatanaka, Tomohiro Hayamizu, Masahiro Hino, Go Ichikawa, Sohei Imajo, Blair Jamieson, Shinsuke Kawasaki, Masaaki Kitaguchi, Ryohei Matsumiya, Kenji Mishima. 2022-07-18. Study of Thin Iron Films for Polarization Analysis of Ultracold Neutrons. https://doi.org/10.7566/jpscp.37.020801

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