是一个类似于烯的分子离子导致了4430安格斯特罗姆的分散星际吸收带吗?
1NASA-Ames Research Center, Space Science Division, Moffett Field, California 94035, USA.
Nature
|July 2, 1992
概括
分散星际带 (DIB) 是天文吸收特征. 实验室测量表明,酸可能是特定DIB的原因,这可能解释了多环芳碳化合物如何处理星际光.
科学领域:
- 天文学和天体物理学
- 天体化学是天体化学.
- 频谱学是一种光谱学.
背景情况:
- 分散星际带 (DIBs) 是天文光谱中的众多吸收特征.
- DIBs的载体仍然未被确定,关于它们是气体还是以谷物为基础的争论仍在进行中.
- 多环芳 (PAH) 是一些DIB载体的分子候选物.
研究的目的:
- 在实验室矩阵中研究烯 (C16H10+) 的光学光谱.
- 将实验室测量的光谱与DIBs的天文观测进行比较.
- 探索PAH离子在星际光处理中的潜在作用.
主要方法:
- 使用子和子矩阵对烯 (C16H10+) 的光学光谱进行实验室测量.
- 吸收特征的分析,包括峰值位置和连续性特征.
- 将光谱数据与已知的天文DIB进行比较.
主要成果:
- 烯离子体表现出一个强烈的吸收特征接近4430安格斯特姆,与一个突出的DIB.对齐.
- 这种特定的DIB,如果归因于类似于pyrene的物种,将需要0.2%的宇宙碳.
- 从紫外线到可见波长的强烈,广泛的连续性被观察到的pyrene离子,类似于naphthalene离子.
结论:
- 烯是4430安格斯特罗姆DIB的一个可信的候选者.
- 酸可能具有共同的连续特征,负责将紫外线/可见星际辐射转换为红外线.
- 这项研究有助于了解星际物质的组成和能量转移过程.
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