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Updated: Jun 30, 2026

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Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
在星际冰中结的分子的光谱检测
S A Sandford1, L J Allamandola, T R Geballe
1NASA/Ames Research Center, Moffett Field, CA 94035, USA.
概括
在向红外源WL5.5的冰中检测到冷的分子和甲醇. 这一发现为星际冰的组成和恒星形成区域的化学成分提供了洞察力.
科学领域:
- * 天体化学 * 天体化学
- * 星际介质的组成
- * 红外光谱学 红外光谱学
背景情况:
- * rho Ophiuchus云集是一个附近的活跃恒星形成区域.
- * 了解星际冰的组成对于追踪太空中的化学进化至关重要.
- *红外光谱是一种强大的工具,用于识别尘埃粒的冰冷地幔中的分子.
研究的目的:
- * 为了识别和描述冰中的分子物种,向红外源WL5.5方向.
- * 为了确定这个视线上的冷分子和甲醇的丰富度.
- * 为了比较冷分子的丰富度与冷一氧化碳的丰富度.
主要方法:
- * 使用高分辨率红外光谱学观察了WL5.5的光谱.
- * 对光谱中的吸收特征的分析允许识别分子物种.
- *检测到的分子的柱密度是从它们的吸收特征的强度计算出来的.
主要成果:
- * 在4141厘米-1 (2.415微米) 的弱红外吸收特征被检测到,该特征归因于冷的分子 (H2).
- *在4125厘米-1 (2.424微米) 的更广泛的吸收可能是由于冰中的甲醇 (CH3OH).
- *推断的柱子密度大约为H2的2.5 x 1018 cm-2和CH3OH的3.0 x 1019 cm-2.
- *发现了大量的冷分子,大约是冷一氧化碳的三倍.
结论:
- *分子,通过辐射形成并在现场结,存在于WL5.5方向的富含水的冰中.
- *这些星际冰中也存在甲醇.
- *相对于二氧化碳,冷H2的丰富性限制了前恒星环境中的冰的形成和处理.
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