Broadband Wide-Angle VElocity Selector (BWAVES) neutron spectrometer designed for the SNS Second Target Station

¹ Second Target Station Project, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
² Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
³ Department of Mechanical Engineering and Materials Science, Department of Physics, and Department of Chemistry, Duke University, Durham, North Carolina 27708 USA
⁴ Department of Chemical and Environmental Engineering, University of Cincinnati, Ohio 45221, USA
⁵ Univ. Grenoble Alpes, CNRS, LiPhy and Institut Universitaire de France, and Institut Laue-Langevin, Grenoble, France
⁶ Department of Chemistry and Department of Physics & Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA
⁷ UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Oak Ridge, Tennessee 37831, Knoxville, Tennessee 37996, USA
⁸ Chemical Sciences Division, Oak Ridge National Laboratory, USA and Department of Chemistry, University of Tennessee, Oak Ridge, Tennessee 37831, Knoxville, Tennessee 37996, USA

^* Corresponding author: mamontove@ornl.gov

Published online: 17 November 2022

Abstract

A recently proposed wide-angle velocity selector (WAVES) device for choosing the velocity of detected neutrons after they have been scattered by the sample paves the way for inverted geometry neutron spectrometers with continuously adjustable final neutron wavelength. BWAVES broadband inverted geometry spectrometer proposed for the Second Target Station at the Spallation Neutron Source at Oak Ridge National Laboratory is designed using WAVES to simultaneously probe dynamic processes spanning 4.5 decades in time (energy transfer). This makes BWAVES a uniquely flexible instrument which can be viewed as either a quasielasitc neutron scattering (QENS) spectrometer with a practically unlimited (overlapping with the vibrational excitations) range of energy transfers, or a broadband inelastic vibrational neutron spectrometer with QENS capabilities, including a range of accessible momentum transfer (Q) and a sufficiently high energy resolution at the elastic line. The new capabilities offered by BWAVES will expand the application of neutron scattering in ways not possible with existing neutron spectrometers.