Polarized neutron imaging using helium-3 cells and a polychromatic beam

We present the use of helium-3 spin filters for polarized neutron imaging of magnetic phenomena. These polarization devices allow improvements in both spatial (factor of 2–3) and temporal (factor of ∼5) resolution compared with previously used solid-state benders. This set-up has been used to visualize small-scale magnetic features in an Fe65.7Co18Si0.8B15.5 foil with a thickness of 21–22 μm and a saturation magnetization of 1.7 T, and trapped magnetic flux in a superconducting lead cylinder.