Development of Pulse Shape Discrimination Techniques for Tritium Production Rate and Fast Neutron Flux Measurement Using a Single Crystal Diamond Based Radiation Detector for the Application of Breeding Blanket Performance Experiments

抄録

In this study, we present a comprehensive description of a single crystal diamond-based detector (SCDD) system equipped with a ⁶Li thermal neutron converter and its radiation detection processes. Based on these processes, several pulse shape discrimination (PSD) methods applicable to the performance evaluation of breeding blankets are proposed. A basic PSD method, using either pulse width or charge integral alone, enables discrimination between gamma-rays and energetic ions produced by the ⁶Li(n,α)³H reaction. This method is therefore suitable for measuring the tritium production rate in a thermal neutron irradiation field. An advanced PSD method, utilizing both pulse width and a specific pulse shape index, effectively rejects gamma-ray signals and extracts pulses originating from fast neutrons and energetic ions produced by the ⁶Li(n,α)³H reaction. Post-analysis of the extracted signals demonstrates that both the tritium production rate and the fast neutron flux can be evaluated simultaneously in a mixed radiation field using a single SCDD. In addition to the intrinsic advantages of SCDD, such as compact size, excellent radiation hardness, and high temperature operability, the PSD methods developed in this study enable broader applications not only in breeding blanket performance evaluation but also across a wide range of scientific research fields.