Probing the dynamics of confined systems with the NIST backscattering spectrometer

Abstract
A new high-resolution backscattering spectrometer, recently commissioned at the National Institute of Standards and Technology Center for Neutron Research is providing new opportunities in the United States for the investigation of the dynamics of condensed matter systems in confinement. The dynamic range (± 35 µeV), flux at the sample position (1.4 x 10 ⁵ n/cm²/s), and instrumental resolution (δE < 1 µeV) allow users to probe dynamics on time scales between 0.1 and 1 ns. Therefore this backscattering spectrometer is an excellent tool for probing the low energy dynamics of confined condensed matter systems. A discussion is presented of the instrument design parameters and its utility in probing dynamics in confinement is illustrated with data from recent measurements.