基于14 MeV中子的烧氚历史诊断模拟研究

针对直接测量16.7 MeV进行烧氚历史诊断所需聚变产额高的情况，模拟研究了利用14 MeV中子与副靶作用产生的非弹伽马进行烧氚历史诊断的情况，计算了几种材料14 MeV中子作用产生的次级伽马能谱以及切伦科夫辐射阈能之上的非弹伽马数目，对副靶材料和厚度进行了选择。计算了14 MeV中子产生的切伦科夫光子时间谱，分析了光电转换器件处伽马、电子以及正电子等噪声信号，分析了气体切伦科夫系统测量统计涨落与聚变中子产额之间的关系，确定了气体切伦科夫系统所适用的最低聚变中子产额，通过测量14 MeV中子与副靶产生的非弹伽马进行烧氚历史诊断较直接测量16.7 MeV伽马可将测量所需聚变中子产额降低2个量级。

Simulation study on DT fusion reaction history diagnosis based on 14 MeV neutron

Measurement of fusion reaction history by detecting the 16.7 MeV gamma-rays needs high neutron yield. For this reason, simulation study for fusion reaction history diagnosis with inelastic gammas generated by 14 MeV neutron interacting with the puck in front of (Gas Cherenkov Detector, GCD) was carried out. Material and thickness of the puck were determined by calculating energy spectrum of the secondary gamma and yield of gammas above the Cherenkov threshold. Cherenkov signal of the inelastic gammas through the GCD generated by interaction of 14 MeV neutron with the puck was simulated. Noises of gammas, electrons and positrons at the photo-electric conversion device were analyzed. Relation of the statistical fluctuations of the Cherenkov detection system and the fusion neutron yield was ascertained. Fusion neutron yield for fusion reaction history diagnosis by detecting 14 MeV neutron can decrease by two magnitudes in comparison with that by directly detecting 16.7 MeV gamma rays.