Unified Analysis of Structure Formations and Evolutions in the Deep Universe

宇宙深处结构形成与演化的统一分析

• 批准号: 10640229
• 负责人: GOUDA Naoteru
• 金额: $ 1.47万
• 依托单位: National Astronomical Observatory of Japan (1999-2000)Osaka University (1998)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10640229/
• 关键词: galaxy formations; large scale structues in the universe; self-gravitating many-body systems

1. We developed a semi-analytic model for resolving the problems of galaxy formations and got some interesting results using this semi-analytic model based on the hierarchical clustering. By using this model, we tried to clarify what physical processes, which have never been taken into account in the galaxy formation models, influence on galaxy formations and evolutions. Furthermore, we tried to constrain the cosmological models and some physical processes concerned in the galaxy formations, such as star formations. The detailed topics on the galaxy formations are shown below.(1) The effects of merging histories of proto-objects on the angular momentum distributions of the present-time dark matter haloes were clarified.(2) We investigated the effects of the UV background radiation on galaxy formations by using the semi-analytic model including the photoionization process and we clarified its effects on the galaxy formations.(3) We calculated the detection rate of cold gas in elliptical … More galaxies using the semi-analytic model of galaxy formation, and compared it with observations. Then we could constrain the star formation rates in the galaxy formations.(4) We clarified the physical origin of the color-magnitude relation of elliptical galaxies in clusters of galaxies in the hierarchical clustering scenario by using the semi-analytic model.(5) The galaxy number counts are analyzed by using the semi-analytic model based on the hierarchical clustering scenario. In this model, we introduced the selection effects due to the rapidly dimming surface brightness at high redshift and the absorption by intergalactic HI clouds and by internal dust, which are not considered in the previous analysis of galaxy counts.2. The relation between relaxation, the time scale of Lyapunov instabilities, and the Kolmogorov-Sinai time in a one-dimensional gravitating sheet is studied. We found that the relaxation time to the final thermal equilibrium differs from the inverse of the Lyapunov exponents and the Kolmogorov-Sinai time.3. We found the relation between the two-point spatial correlation function and the density profile of the dark matter halos in the strongly nonlinear regime. Less

1.我们建立了一个解决星系形成问题的半解析模型，并利用这个基于层次聚类的半解析模型得到了一些有趣的结果。通过使用这个模型，我们试图弄清楚在星系形成模型中从未考虑到的物理过程对星系形成和演化的影响。此外，我们试图约束宇宙学模型和星系形成中涉及的一些物理过程，例如恒星形成。具体内容如下：(1)阐明了原始天体合并历史对现今暗物质晕角动量分布的影响。(2)利用包含光电离过程的半解析模型研究了UV背景辐射对星系形成的影响，阐明了它对星系形成的影响。(3)计算了椭圆…中冷气的探测率更多的星系使用半解析的星系形成模型，并将其与观测结果进行比较。利用半解析模型阐明了等级星系团中椭圆星系颜色-星等关系的物理来源。(5)利用基于等级星系团场景的半解析模型分析了星系数目。在这个模型中，我们引入了由于高红移时表面亮度迅速变暗以及被星系间HI云和内部尘埃吸收而产生的选择效应，这在以前的星系计数分析中是没有考虑的。研究了一维引力片中的弛豫、Lyapunov不稳定性的时间尺度和Kolmogorov-Sinai时间之间的关系。我们发现，达到最终热平衡的驰豫时间与Lyapunov指数和Kolmogorov-Sinai时间的倒数不同。我们发现了在强非线性区域两点空间关联函数与暗物质晕密度分布之间的关系。较少

项目成果

Yutaka Fujita, Masahiro Nagashima and Naoteru Gouda: "The Detection Rate of Molecular Gas in Elliptical Galaxies : Constraints on Galaxy Formation Theories"Publication of Astronomical Society of Japan. 52. 743-748 (2000)

Yutaka Fujita、Masahiro Nagashima 和 Naoteru Gouda：“椭圆星系中分子气体的探测率：对星系形成理论的限制”日本天文学会出版。

Masahiro Nagashima and Naoteru Gouda: "Effects of Merging Histories on Angular Momentum Distribution of Dark Matter Haloes"Mon.Not.R.Astro.Soc.. 301. 849-860 (1998)

Masahiro Nagashima 和 Naoteru Gouda：“合并历史对暗物质晕角动量分布的影响”Mon.Not.R.Astro.Soc.. 301. 849-860 (1998)

Masahiro Nagshima and Naoteru Gouda: "Effects of Merging Histories on Angular Momentum Distribution of Dark Matter Haloes"Mon.Not.R.Astro.Soc.. 301. 849-860 (1998)

Masahiro Nagshima 和 Naoteru Gouda：“合并历史对暗物质晕角动量分布的影响”Mon.Not.R.Astro.Soc.. 301. 849-860 (1998)

Masahiro Nagashima: "Effects of the UV Background Radiation on Galaxy Formation"Monthly Notice of Royal Astronomical Society. 305. 849-860 (1999)

长岛正宏：“紫外线背景辐射对星系形成的影响”英国皇家天文学会月刊。

Masahiro Nagashima,Naoteru Gouda and Norimasa Sugiura: "Effects of the UV background radiation on Galaxy Formation"Mon.Not.R.Astro.Soc.. 305. 449-456 (1999)

Masahiro Nagashima、Naoteru Gouda 和 Norimasa Sugiura：“紫外线背景辐射对星系形成的影响”Mon.Not.R.Astro.Soc.. 305. 449-456 (1999)