Cold Neutron Beams from Small Low-Temperature Moderators in Reactors

An investigation has been made of the efficiency of several hydrogenous low-temperature moderators in the production of intense cold neutron beams from reactors. The dimensions of such a moderator are usually severely limited, but even small volumes of liquid hydrogen, liquid hydrogen deutride, and solid methane were effective. A qualitative theoretical explanation is given of the degree of moderation observed.