惊人的中子捕获截面是88Zr
Jennifer A Shusterman1,2,3, Nicholas D Scielzo4, Keenan J Thomas4
1Lawrence Livermore National Laboratory, Livermore, CA, USA. js7294@hunter.cuny.edu.
Nature
|January 9, 2019
概括
研究人员测量了88Zr放射性核的中子捕获截面. 测量值为86.1万,远大于预测值,强调需要更多的放射性同位素核数据.
科学领域:
- 核物理
- 核天体物理学
- 核安全问题
背景情况:
- 对于理解核反应至关重要.
- 对于88Zr等放射性同位素的数据很少,而且经常存在很大的不确定性.
- 88Zr对于核安全应用非常重要.
研究的目的:
- 通过实验确定88Zr的热中子捕获截面.
- 将实验结果与理论预测进行比较.
- 调查这项测量对核科学的影响.
主要方法:
- 暴露88Zr在核反应堆中的强烈中子流.
- 使用放射性产品发出的玛射线的敏感检测测量中子捕获截面.
- 利用目标 (88Zr) 和产品 (89Zr) 核的放射性进行检测.
主要成果:
- 确定88Zr的热中子捕获截面为861,000±69,000 barns.
- 这个值比理论上预测的10个仓库大五倍.
- 这是迄今为止测量到的第二大热中子捕获截面,
结论:
- 88Zr的试验截面非常大,挑战现有的理论模型.
- 这一发现突显了中子捕获放射性同位素的突发发现的潜力.
- 未来使用新设施的测量可能会揭示更多的惊喜,对核科学产生重大影响.
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