Neutron Kikuchi Effect and Practical Problems Associated with Its Observation

The theory of the neutron Kikuchi effect has been re-examined and an exact formulation in reciprocal space derived. The conditions necessary for its observation have been considered and appropriate data from a lead single crystal have been collected on the triple-axis spectrometer at the HIFAR reactor in the laboratories of the Australian Nuclear Science and Technology Organisation. A series of constant-Q phonon scans across the predicted positions of the Kikuchi lines show reductions in the integrated phonon intensity, which appear to move as expected with changes in the scattered neutron wavevector.