Implementation of cross correlation for energy discrimination on the time-of-flight spectrometer CORELLI

J Appl Crystallogr. 2018 Mar 26;51(Pt 2):315-322. doi: 10.1107/S160057671800403X. eCollection 2018 Apr 1.

Abstract

The CORELLI instrument at Oak Ridge National Laboratory is a statistical chopper spectrometer designed and optimized to probe complex disorder in crystalline materials through diffuse scattering experiments. On CORELLI, the high efficiency of white-beam Laue diffraction combined with elastic discrimination have enabled an unprecedented data collection rate to obtain both the total and the elastic-only scattering over a large volume of reciprocal space from a single measurement. To achieve this, CORELLI is equipped with a statistical chopper to modulate the incoming neutron beam quasi-randomly, and then the cross-correlation method is applied to reconstruct the elastic component from the scattering data. Details of the implementation of the cross-correlation method on CORELLI are given and its performance is discussed.

Keywords: cross-correlation technique; energy discrimination; neutron diffraction; time-of-flight neutron beamlines.

Grants and funding

This work was funded by U.S. Department of Energy, Basic Energy Sciences grant . U.S. Department of Energy, Office of Science grant .