Preparation for a neutronics experiment using a discharge fusion device and an imaging plate neutron detector

Abstract

Tritium breeding ratio (TBR) is one of the most important parameters determining the tritium self-sufficiency of a deuterium-tritium fusion reactor. A neutronics experiment is planned to measure the spectral neutron fluences two-dimensionally (2D) using a discharge-type compact fusion neutron source and a neutron imaging plate (NIP), respectively. We report a calibration method for the NIP and optimization of the discharge condition to enhance the neutron production rate. A linear relationship between the neutron fluence in the NIP and photostimulated luminescence (PSL) per area was obtained in the range of the neutron fluence from 10³ to 10⁷ n/cm². A neutron production rate higher than 10⁷ n/s was successfully achieved by the optimized discharge condition. It is shown that a quantitative 2D measurement by the NIP is feasible using the linear relationship and a correlation coefficient on the energy spectrum.