作为月球大气中的大量来源的光子刺激脱落
1Department of Physics and Astronomy, Rutgers, The State University of New Jersey, Piscataway 08854-8019, USA.
Nature
|August 24, 1999
概括
以光子刺激的脱吸有效地从月球表面释放了原子. 这种由紫外线驱动的过程是月球薄弱大气层的重要来源,热溶解对水星也很重要.
科学领域:
- 行星科学 行星科学
- 大气化学 大气化学
- 表面物理 表面物理
背景情况:
- 水星和月球拥有含有原子和的微薄大气.
- 这些元素需要不断补给,因为保留时间 (小时) 很短.
- 拟议的补给机制包括喷,冲击,热消化和光子刺激的消化,主要过程不清楚.
研究的目的:
- 为了研究从模拟的月球酸盐表面中光子刺激的溶解.
- 为了确定由紫外线光子诱导的原子释放的效率和机制.
- 为了评估光子刺激脱吸对月球和水星大气的贡献.
主要方法:
- 实验室实验模拟月球表面条件.
- 用紫外线光子 (波长<300 nm) 轰炸酸盐表面,波长约为250 K.
- 通过电子刺激诱导的原子脱吸的分析.
主要成果:
- 从模拟的月球表面对的光子刺激脱离是非常高效的.
- 脱吸主要是由电子刺激驱动的,而不是热过程或动量转移.
- 紫外线光子的太阳流足以对月球大气中的有显著的贡献.
结论:
- 光子刺激的脱吸是向月球大气中供应的关键过程.
- 在水星上,光子刺激和热溶解都可能对大气中的很重要.
- 了解这些表面-大气相互作用对于行星科学至关重要.
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