Study on neutrons moderation in parrafin layers

Neutrons from Am-Be source have to be moderated down in paraffin to the epithermal and thermal energy ranges. The study focuses on determining the profiles of both neutrons groups in a designed paraffin column isolated from surroundings thermal neutrons by a cadmium box. The neutron fluxes were measured by activation method with Ag-foils. The activities of the Ag-foils were determined by beta semiconductor detector conducted with the PC Fast Multichannel Scaling Board AccuSpec. The experimental data were described by the exponential saturate function of the energy transfer process. (author)