VLAD for epithermal neutron scattering experiments at large energy transfers

Abstract

The Very Low Angle Detector (VLAD) bank will extend the kinematical region covered by today's epithermal neutron scattering experiments to low momentum transfer (<10 Å−1) together with large energy transfer <1 eV. Such kinematical region is so far unexplored and will allow for new experimental studies in condensed matter systems. VLAD is at present being commissioned on the VESUVIO spectrometer at the ISIS pulsed neutron source. It consists of an array of Resonant Detectors covering the scattering range 1°-4°. In this paper the design of VLAD is presented together with Montecarlo simulations of the detector performances. The results of tests made with prototype VLAD detectors are also presented, confirming the usefulness of the Resonance Detector for measurements at very low scattering angles.