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在太阳风中对和同位素分离的限制
Alex Meshik1, Jennifer Mabry, Charles Hohenberg
1Physics Department, Washington University, St. Louis, MO 63130, USA. am@physics.wustl.edu
概括
创世纪任务发现太阳风的同位素成分与太阳表面密切匹配. 这表明最小的分成,支持一个统一的太阳星云行星形成,虽然地球的不同.
科学领域:
- 行星科学 行星科学
- 太阳物理 太阳物理
- 太空化学 太空化学
背景情况:
- 了解太阳星云的同位素组成对于行星形成理论至关重要.
- 创世纪任务的目的是直接采样太阳风,与太阳表面材料进行比较.
- 太阳风和太阳之间的同位素变化 (分离) 可能表明复杂的过程.
研究的目的:
- 为了评估太阳星云的同位素组成.
- 为了确定太阳风同位素和太阳表面同位素之间的关系.
- 为了检查太阳风和太阳表面材料之间的同位素变化.
主要方法:
- 由创世纪发现任务返回的独立太阳风样本的分析.
- 高精度测量同位素 (20Ne/22Ne) 和同位素 (36Ar/38Ar).
- 来自不同太阳风系统和地球大气的同位素比率的比较.
主要成果:
- 在20Ne/22Ne和36Ar/38Ar比率中没有观察到显著的方案间差异.
- 测量到的低速和高速太阳风之间的20Ne/22Ne差异为0.24 +/- 0.37%.
- 测量36Ar/38Ar低速和高速太阳风之间的差异为0.11 +/- 0.26%.
- 太阳风36Ar/38Ar比率是3.42 +/- 0.09%高于地球大气比率.
结论:
- 太阳风的同位素组成密切地反映了太阳表面的同位素组成.
- 这支持了太阳风和太阳物质之间的最小同位素分离的假设.
- 在36Ar/38Ar中观察到的差异可能表明地球上的早期大气损失.
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