捕获反应的验证在252Cf(s.f.) 中的截面. 中子场中子场的中子场
Martin Schulc1, Evžen Novák1, Jan Šimon1
1Research Centre Rez Ltd, 250 68 Husinec-Řež 130, Czech Republic.
概括
这项研究将实验中子捕获反应速率与核数据库进行了比较. 这些差异突出了核数据需要改进的领域,特别是和反应.
科学领域:
- 核物理 核物理 核物理
- 中子捕捉反应的反应
- 核数据评估的核数据评估
背景情况:
- 中子捕获反应对于核技术应用至关重要.
- 准确的核数据库对于可靠的模拟是必不可少的.
- 以前的评估可能在高能中子范围有局限性.
研究的目的:
- 为了实验性地确定各种同位素的中子捕获反应速率.
- 将实验结果与最先进的核数据库进行比较 (IRDFF-II,ENDF/B-VIII.0,JENDL-5,JEFF-3.3).
- 识别差异并评估不同核数据库的性能.
主要方法:
- 使用标准的加利福尼亚-252 (Cf-252) 自发裂变中子场.
- 采用屏蔽,以专注于高能中子捕获反应.
- 测量了包括黄金 (Au),铜 (Cu), (Sc), (Ta), (Ce), (La), (Yb), (Mn) 和 (Pr) 在内的同位素的反应速度.
- 进行了蒙特卡罗 N-粒子 eXtended (MCNP6.2) 运输代码模拟以进行比较.
主要成果:
- 黄金 (Au) 和铜 (Cu) 的实验反应速率与所有评估的图书馆有很好的一致性.
- 在所有图书馆中,观察到 (Mn) 和 (La) 反应的显著差异.
- 对于大多数反应,JENDL-5库表现出很好的一致性,除了扫 (Sc).
- (Ta) 反应率与所有图书馆在实验不确定性范围内存在分歧.
- (Yb) 的反应速率与JENDL-5和ENDF/B-VIII.0一致,但与JEFF-3.3.3不同.
- (Ce) 和 (Pr) 的反应速率与JEFF-3.3和ENDF/B-VIII.0图书馆不同.
结论:
- 该研究确定了当前核数据库表现出显著差异的特定同位素和反应.
- JENDL-5显示出有前途的性能,但需要进一步验证,特别是对于.
- 对于某些捕获反应,ENDF/B-VIII.0和JEFF-3.3库需要改进,特别是对于,,和.
- 这些发现为改进高能中子应用的核数据库提供了有价值的反.
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