在太阳内部温度下,铁不透明度的测量高于预测
J E Bailey1, T Nagayama1, G P Loisel1
1Sandia National Laboratories, 1515 Eubank SE, Albuquerque, New Mexico 87185-1196, USA.
Nature
|January 6, 2015
概括
新的实验室测量显示,在太阳内部条件下,铁的不透明度明显高于预测. 这一发现有助于解决太阳模型和日震观测之间的差异,改善我们对恒星结构的理解.
科学领域:
- 等离子体物理学的物理学
- 恒星天体物理学 恒星天体物理学
- 原子物理 原子物理
背景情况:
- 恒星内部温度概况由辐射吸收 (不透明度) 控制.
- 之前的不透明度测量没有在恒星内部实际条件下进行,这导致恒星模型的不确定性.
- 修订的太阳能元素丰度与日热地震数据相冲突,这表明需要更高的内部不透明度.
研究的目的:
- 在模仿太阳辐射/对流区边界的条件下实验测量铁的不透明度.
- 为了解决标准太阳模型与日热地震观测之间的差异.
- 调查铁不透明在解决太阳模型不确定性的作用.
主要方法:
- 实验室测量波长解析的铁不透明度.
- 模拟的太阳内部条件,电子温度为1.9-2.3万K,电子密度为 (0.7-4.0) × 10^22cm−3.3.
- 专注于与太阳辐射/对流带边界相关的条件.
主要成果:
- 测量波长依赖的铁不透明度比理论预测高30-400%.
- 这些结果表明,铁对整体不透明度差异的贡献很大.
- 测量的增加约占平均不透明度所需变化的一半,以使太阳能模型与日热地震学相协调.
结论:
- 实验性的铁不透明度测量提供了精细化恒星模型的关键数据.
- 铁的不透明度高于预测,为太阳能建模差异提供了部分解决方案.
- 需要对其他元素进行进一步的不透明度测量,以完全解决太阳内部的不确定性.
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