title: New fabrication method for an ellipsoidal neutron focusing mirror with a metal substrate.
abstract: We propose an ellipsoidal neutron focusing mirror using a metal substrate made with electroless nickel-phosphorus (NiP) plated material for the first time. Electroless NiP has great advantages for realizing an ellipsoidal neutron mirror because of its amorphous structure, good machinability and relatively large critical angle of total reflection for neutrons. We manufactured the mirror by combining ultrahigh precision cutting and fine polishing to generate high form accuracy and low surface roughness. The form accuracy of the mirror was estimated to be 5.3 μm P-V and 0.8 μm P-V for the minor-axis and major-axis direction respectively, while the surface roughness was reduced to 0.2 nm rms. The effect of form error on focusing spot size was evaluated by using a laser beam and the focusing performance of the mirror was verified by neutron experiments.
authors.forename: Jiang
authors.initials: J
authors.lastname: Guo
authors.forename: Shin
authors.initials: S
authors.lastname: Takeda
authors.forename: Shin-ya
authors.initials: SY
authors.lastname: Morita
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hino
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Oda
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Kato
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yamagata
authors.forename: Michihiro
authors.initials: M
authors.lastname: Furusaka