首次测量了重离子储存环中反向动力学替代反应的中子发射概率
M Sguazzin1, B Jurado1, J Pibernat1
1Université de Bordeaux, CNRS, LP2I Bordeaux, 33170 Gradignan, France.
Physical review letters
|March 7, 2025
概括
测量短寿命核的中子捕获截面是具有挑战性的. 这项研究成功地在重离子储存环中使用了一种新的替代反应方法,以获得恒星核合成和社会应用的关键数据.
科学领域:
- 核天体物理学 核天体物理学
- 实验核物理实验核物理
- 重元素的核合成重元素的核合成
背景情况:
- 精确的中子诱导反应截面对于理解恒星中的重元素起源和技术应用至关重要.
- 由于目标核的放射性,直接测量是很困难的,需要替代实验方法.
- 替代反应与重离子储存环相结合,为克服这些测量挑战提供了一个有希望的解决方案.
研究的目的:
- 通过使用重离子储存环在逆动力学中进行第一个替代反应实验.
- 测量中子发射概率作为Pb核激发能量的函数.
- 确定中子诱导辐射捕获截面,用于Pb,目前没有实验数据.
主要方法:
- 使用了GSI/FAIR设施的实验储存环 (ESR).
- 在逆动力学中使用Pb{208}Pb(p,p^{'}) 反应作为对Pb的中子捕获的替代物.
- 利用高检测效率来测量中子辐射概率.
主要成果:
- 在重离子储存环上成功进行了第一个反向动力学替代反应实验.
- 首次测量了中子发射概率与 ^{208} Pb. 的激发能量.
- 提供了对中子诱导辐射捕获截面的可靠结果 ^{207}Pb.
结论:
- 与重离子储存环相结合的替代反应方法是测量放射性核的横截面的可行技术.
- 获得的关于中子发射概率的数据允许选择合适的核模型.
- 这项研究显著提高了我们研究核合成的能力,并开发了需要有关短寿命核的数据的应用程序.
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