在大质量恒星中增强60Fe的产生
A Spyrou1,2, D Richman3,4, A Couture5
1Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI, USA. spyrou@frib.msu.edu.
Nature communications
|November 6, 2024
概括
大质量恒星会喷射出铁-60 (60Fe) 和-26 (26Al) 等元素. 新的实验表明60Fe的产量高于预期,扩大了观测和模型之间的差距,表明大质量恒星天体物理学存在问题.
科学领域:
- 核天体物理学 核天体物理学
- 恒星进化中的恒星演变
- 太空化学丰富的宇宙化学丰富
背景情况:
- 大质量恒星是宇宙化学元素的主要来源,通过恒星风和超新星.
- 长寿命的放射性同位素,铁-60 (60Fe) 和-26 (26Al),作为银河系核合成的标记物.
- 观察到的和预测的60Fe/26Al比率之间存在着持续的差异,这影响了我们对恒星过程的理解.
研究的目的:
- 为了实验性地限制对铁-59 (59Fe) 的中子捕获反应,这是60Fe生产模型中一个关键的不确定性.
- 根据新的实验数据,重新评估大质量恒星中的60Fe产量.
- 调查修订60Fe生产对观察到的60Fe/26Al比率的影响.
主要方法:
- 在59Fe.Fe.上精确测量了中子捕获截面.
- 将实验数据集成到核合成网络计算中.
- 模型预测与玛射线望远镜观测数据的比较.
主要成果:
- 实验结果对59Fe (n,γ) 60Fe反应速率提供了强烈的约束.
- 这项研究表明,大质量恒星的60Fe产量比以前估计的要高.
- 这些发现进一步放大了60Fe/26Al比率的差异.
结论:
- 核不确定性,特别是59Fe(n,γ) 60Fe反应,不能单独解释观察到的60Fe/26Al比率.
- 持续存在的差异指向了当前大质量恒星进化模型中的基本问题.
- 需要修订恒星模型,以使理论预测与银河系化学进化观测相协调.
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