Polarized 3He analyzers for neutron reflectometry

At the National Institute of Standards and Technology (NIST) and Indiana University, we are developing polarized He-3 analyzers for neutron reflectometry. We have employed He-3 analyzers at two polarized neutron reflectometers, NG1 at the NIST Center for Neutron Research (NCNR) and POSY I at the Intense Pulsed Neutron Source (IPNS), Argonne National Laboratory. The long-term goal for both efforts is to perform efficient studies of magnetic diffuse scattering. At the NCNR, we tested a He-3 analyzer by comparing measurements of specular scattering obtained with a supermirror analyzer to those obtained with a He-3 analyzer. For this test, we measured the spin-flip and nonspin-flip scattering from a Mn0.52Pd0.48/Fe thin film. The results with the He-3 analyzer show very good agreement with those obtained with the supermirror analyzer. We have Also carried out tests of the He-3 analyzer for application to magnetic diffuse scattering experiments. We discuss the development of a He-3 analyzer for IPNS that will be employed. for studies of patterned magnetic arrays. (C) 2003 Elsevier Science B.V. All rights reserved.