星际碳化硅SiC尘埃

发布时间：2018-01-19 23:45

本文关键词： 碳化硅 .μm特征碳星红外光谱　出处：《中国科学:物理学力学天文学》2016年07期 　论文类型：期刊论文

【摘要】：碳化硅(SiC)尘粒是宇宙尘埃的重要成分之一,亚微米尺寸的SiC颗粒在11.3μm波长附近有非常显著的晶格振动带.早在20世纪60年代,Friedemann等人就预言了SiC尘粒可以冷凝在富碳恒星的质量流失喷出物中.随后,通过11.3μm的光谱特征,在碳星的星周包层检测到了SiC尘埃.另外,通过原始陨石中同位素异常发现前太阳(Presolar)SiC尘粒最终确立了SiC在星际介质中的存在.然而,令人困惑的是,在星际空间中并未观测到SiC的11.3μm吸收特征.本文主要介绍SiC的光学性质、SiC在天体环境中的观测特征,从而推断SiC在星际空间的丰度上限,并对其在星际空间中的演化进行理论分析.
[Abstract]:Silicon carbide (sic) dust particles are one of the most important components of cosmic dust. Submicron size SiC particles have very significant lattice vibration bands near the wavelength of 11. 3 渭 m, as early as 1960s. Friedemann et al. predicted that SiC dust particles could be condensed in mass loss ejections from carbon-rich stars, and then passed through a spectral characteristic of 11.3 渭 m. SiC dust was detected in the circumstellar envelope of the carbon star. Through isotopic anomalies in primitive meteorites, it was found that the Presolarar sic dust particles eventually established the existence of SiC in interstellar media. 11.3 渭 m absorption characteristics of SiC have not been observed in interstellar space. The optical properties of SiC and sic in celestial environment are introduced in this paper. The upper limit of SiC abundance in interstellar space is deduced, and its evolution in interstellar space is analyzed theoretically.
【作者单位】：湘潭大学物理与光电工程学院;美国密苏里大学物理和天文学系;
【基金】：国家自然科学基金资助项目(编号:11273022,11473023,U1531108)
【分类号】：P148
【正文快照】： 在浩瀚的星系宇宙中,除了恒星、行星、彗星等各种天体之外,在恒星与恒星之间,还存在一种由气体和微小的固体颗粒组成的物质即星际介质.这些固体尘埃颗粒虽然只占星系星际物质总质量的约百分之一,但是在星系演化、恒星和行星系统的形成,乃至生命的起源中都有着极为重要的作用.

【相似文献】