Diffuse neutron scattering from an ω-phase ZrNb alloy

A back-scattering neutron spectrometer with an energy resolution of ～2μeV (FWHM) has been used to measure the diffuse quasielastic scattering from the ω-phase of Zr_1-xNb_x (0.18 < x < 0.19). It is found that the intrinsic energy-width of the scattering does not change between room temperature and 1000 K. At both temperatures the width is less than ～0.2μeV and consistent with zero.