The Solution of Cold Neutron Source using Solid Methane Moderator for the CPHS

The Compact Pulsed Hadron Source (CPHS) at Tsinghua University will produce neutrons by bombarding a 13-MeV proton beam from a LINAC system on a beryllium target. One of the purposes of this neutron source is to provide the neutron facilities for characterization of advanced materials with an emphasis on soft matter and biological systems, for which high cold-neutron fluxes are essential. The design and optimization of the solid-methane moderator system aim at the enhancement of cold neutron production. This paper describes the moderator configuration, the associated gas-handling and cryogenic apparatus, and the operation procedure.