UV-induced diamond formation in interstellar clouds

星际云中紫外线诱导钻石形成

• 批准号: 15340180
• 负责人: KOUCHI Akira
• 金额: $ 10.82万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15340180/
• 关键词: diamond; carbonaceous chondrites; interstellar; clouds; amorphous ice; 有機物; プレソーラーダイヤモンド; 隕石

New formation routes of diamond in interstellar clouds and parent bodies of carbonaceous chondrites are found based on laboratory experiments. It is shown that diamond precursor nucleated as a result of UV photolysis of interstellar ice mixtures in molecular clouds, and grew with further UV irradiation in diffuse clouds. The present study supports the occurrence of diamonds in interstellar clouds, and suggests that diamond is ubiquitous in space. Furthermore, we performed experiments on the aqueous alteration and the subsequent thermal metamorphism of organic materials formed in molecular cloud, and found that diamonds formed by this process in the parent bodies of carbonaceous chondrites. The various characteristics of nano-diamonds in chondrites and interplanetary dusts are well explained by these new formation routes.

在实验室实验的基础上，发现了星际云和碳质球粒陨石母体中金刚石形成的新途径。结果表明，金刚石前驱体是由于分子云中星际冰混合物的紫外光分解而成核的，并随着漫射云中紫外线的进一步照射而生长。目前的研究支持星际云中存在钻石，并认为钻石在太空中无处不在。此外，我们还对分子云中形成的有机物质的水蚀变和随后的热变质作用进行了实验，发现在碳质球粒陨石母体中通过这个过程形成了钻石。这些新的形成途径很好地解释了球粒陨石和星际尘埃中纳米钻石的各种特征。

项目成果

Evaporation of interstellar organic materials in the solar nebula

太阳星云中星际有机物质的蒸发

• 发表时间: 2003
• 期刊: Astrophys.J. 592
• 作者: Nakano;H.
• 通讯作者: H.

Observation of resonance structures in 4d photoionization of Eu

Eu 4d 光电离共振结构的观察

• DOI: 10.1016/j.elspec.2005.01.209
• 发表时间: 2005
• 作者: T. Kojima;F. Chen;M. Kitajima;T. Koizumi;Y. Nakai;H. Yamaoka;N. Watanabe
• 通讯作者: N. Watanabe

Watanabe N.: "Thedependence of H2CO and CH3OH formation on the temperature and thickness of H2O-CO ice during successive hydrogenetion of CO"Astrophys.J.. 588. L121-L124 (2003)

Watanabe N.：“CO 连续氢化过程中 H2CO 和 CH3OH 形成对 H2O-CO 冰的温度和厚度的依赖性”Astrophys.J.. 588. L121-L124 (2003)

Is Chaos on Europa caused by crust-penetrating impacts?

木卫二上的混乱是由地壳穿透撞击造成的吗？

• 发表时间: 2005
• 期刊: LPSC XXXVI(in press)
• 作者: Cox;R.
• 通讯作者: R.

Nakano, H.: "Evaporation of interstellar organic materialsin the solar nebula"Astrophys.J.. 592. 1252-1262 (2003)

Nakano, H.：“太阳星云中星际有机物质的蒸发”Astrophys.J.. 592. 1252-1262 (2003)