Neutron Response Calculations of Alpha-Track Detector for Fusion Neutronics Applications

The neutron energy dependent response of the α-track detector, cellulose nitrate film (Kodak LR-115 type I) in contact with a lithium radiator was calculated. The “mean effective thickness L _eff” of the radiator is obtained as a function of the neutron energy and incident angle. The distribution of the etched-through-track density is evaluated from the calculated L _eff and compared with the measured results in the fusion blanket assembly.     

CFETR水冷陶瓷增殖剂包层模块产氚率实验验证

水冷陶瓷增殖剂（WCCB）包层作为中国聚变工程试验堆（CFETR）候选包层之一,承担着氚增殖、核热提取、屏蔽等重要涉核功能,其中子学设计的可靠性直接影响CFETR氚自持目标的实现。为验证中子学设计工具,即MCNP和FNEDL3.0数据库,在WCCB包层中子学设计中的可靠性,基于研制出的WCCB包层模块,在DT中子环境下开展中子学实验,对以产氚率（TPR）为代表的中子学参数进行了模拟值（C）和实验值（E）对比分析。结果表明,模块中轴线位置处TPR的C/E为0.97?1.08,而模块边缘位置处TPR的C/E为0.65?0.82;模块钛酸锂层边缘区197Au（n,γ）198Au反应率的C/E为0.72?0.90,表明模块边缘区存在非期望的散射中子,导致该区TPR模拟值和实验值偏离较大。     

Application of a 6LiF Small Neutron Detector with an Optical Fiber to Tritium Production Rate Measurement in D-T Neutron Fields

⁶LiF small neutron detectors with an optical fiber have been used to measure ⁶Li(n,α)T reaction rate distributions at thermal research reactors and accelerator facilities. In the present study, we developed an experimental method for the measurement of tritium production rate (TPR) of ⁶Li using this small detector in deuterium-tritium (D-T) neutron fields. Reaction rate measurements with the detector were conducted in the D-T neutron fields at the Fusion Neutronics Source (FNS) facility. From the results, we determined that this detector can be used to measure the TPR distribution in soft neutron spectrum fields such as in a Be assembly. It is difficult to obtain ⁶Li(n,α)T reaction rate separately in hard neutron spectrum fields such as in a Li₂O assembly, because many kinds of charged particle production reactions need to be taken into consideration. However, a time-dependent reaction rate measurement method combined with the ⁶LiF detector and the ZnS detector is effective to separate the ⁶Li(n,α)T reaction from other reactions even in a hard spectrum field, and it can be applied to the measurement of the TPR distribution accurately.     

可逆比热容法测量反应堆中子注量率的可行性及应用前景

热分析仪器和测量技术的迅速发展为通过测量受辐照材料热性质的变化测量中子注量提供了可能。本文提出采用调制差示扫描量热（MDSC）法测量反应堆辐照的含硼材料可逆比热容的变化,进而得到反应堆的中子注量率。从理论和实验两方面讨论了利用该方法测量反应堆中子注量率的可行性。介绍了可逆比热容法测量反应堆中子注量率的原理和实验方法。展望了这种测量方法在测量高注量反应堆中子注量率的应用前景。