Tunable magnetostatic cavity for housing a 3He neutron spin filter

Abstract

A new design of a magnetostatic cavity for housing a neutron spin filter with spin-polarized 3He gas at a neutron instrument is proposed. Movable components made of soft magnetic materials allow for an accurate tuning of the homogeneity of the holding magnetic field within the cavity and, thus, ensure a long 3He spin relaxation time. In addition, this design enables to correct the holding field in the presence of an external magnetic source near the cavity, which is usually the case in neutron experiments with polarization analysis. © Published under licence by IOP Publishing Ltd.