A Design and its Validation of a Proton Recoil Telescope with a Silicon Detector for Measurements of Fast Neutrons

摘要

A silicon detector combined with a thin polyethylene converter and a collimator is designed as a simple proton recoil telescope (PRT) detector for detecting 2.45 MeV neutrons from a D-D neutron generator. Monte Carlo simulations are performed for a quantitative optimization of the geometrical parameters of the detector that determine the statistics and the spectrum of recoil protons. On the basis of the optimized geometry, a 15 μm polyethylene converter and a 2.5 mm thick stainless steel collimator are chosen for the design of a PRT. A test experiment is done by using 2.45 MeV neutrons from a D-D generator at the Korea Research Institute of Standards and Science. Energy calibration of the silicon detector is done by using proton beams from the MC-50 cyclotron at the Korea Institute of Radiological & Medical Sciences. A peak corresponding to 2.45 MeV neutrons is observed. Neutron detection efficiency of our PRT detector for 2.45 MeV neutrons is found to be about 3 × 10_(?6).