Development of Time-of-Flight Polarized Neutron Imaging at the China Spallation Neutron Source

A time-of-flight polarized neutron imaging setup was realized by integrating an in situ pumped polarized He-3 spin filter and energy dispersive neutron camera on the neutron technique development beamline (BL-20) of the China Spallation Neutron Source (CSNS). Test experiments were performed with a solenoid with aluminum wire as a sample. These demonstrated that polarized radiography with a field of view in diameter 2.0 cm at different wavelengths can be obtained. The wavelength-dependent polarization was used to distinguish the neutron polarization behavior for different positions inside and outside the solenoid. The results of this work show the possibility of applying the technique at CSNS and marks a milestone for future polarized neutron imaging developments.