High-resolution diffraction using Larmor precession of polarized neutrons

Abstract

A new Larmor precession device, consisting of two separate precession modules, is introduced. It operates as a high-resolution neutron diffractometer, without the need for a highly collimated beam, necessary in conventional high-resolution neutron diffraction. The same instrument operates in different modes as an effective small-angle scattering device or accurately determines the line profile, the lattice plane orientation or the angular spread in crystal orientations. A dramatic intensity gain can be obtained in all applications discussed, compared with the conventional analogues, owing to the possibility to use a relaxed wavelength and angular resolution. Experiments in the high-resolution diffraction mode on Si and Al are discussed.