Mechanical neutron beam filter

Abstract

We propose a new mechanical device allowing limiting the visibility time of the neutron source. In the case of pulsed neutron sources, the filter time window can be synchronized with the neutron pulse and thus limits the passage of background neutrons emitted before and after the main neutron pulse. The performance of such filter is analyzed by Monte-Carlo simulations using VITESS software package. It is shown that the proposed filter improves the time resolution of the time-of-flight technique in comparison with disk chopper; associated intensity losses are estimated.