Comparison of Bragg-Edge neutron-transmission spectroscopy at ISIS and LANSCE

The Bragg edges appearing in the neutron-transmission spectra of a polycrystalline material represent its coherent-scattering response at 2θ=180°. Structural information such as texture, phase content or strain may be derived from the intensity and position of these edges. Transmission diffractometers have been recently developed at both LANSCE and ISIS and used for studying the dynamics of phase transformations and strain imaging, respectively. The incident neutron spectra vary due to the different neutron moderators and flight paths used in the two instruments. This paper reports a comparative study of the two instruments and their analysis software.