Pulse characteristics of epithermal neutrons from a spallation source

This paper discusses the feasibility of the use of epithermal neutrons from hydrogen moderators installed at a MW-class spallation neutron source. Pulse characteristics of epithermal neutrons at Japanese Spallation Neutron Source (JSNS) are studied by comparing with a reference light water moderator, which does not exist but is optimized at the JSNS target-moderator-reflector geometry. The performance in figure of merit expected from the JSNS hydrogen moderators at an epithermal neutron region are found to be 50–100%, depending on the neutron energy, compared to the reference light water moderator. JSNS could also be useful as an epithermal neutron source, although it was mainly designed as a cold and thermal neutron sources for the condensed matter research.