Neutron Polarization

The production of polarized neutrons in magnetized iron has been studied, using the intense neutron beams available at the Argonne heavy water pile. The theoretical work of Halpern et al., used as a guide in the experiments, has been checked in many respects, with the exception that the polarization cross section $p$ has a measured value of 3.15 barns compared to the theoretical 1 barn. The application of neutron polarization to the measurement of the approach to saturation in ferromagnets is described and preliminary results are reported.