强引力透镜及其宇宙学约束
发布时间：2019-01-27 11:39
【摘要】：精确的天文观测数据表明当前的宇宙正处于加速膨胀状态,近年来解释宇宙加速膨胀的暗能量已经成为宇宙学研究的热点问题。然而对暗能量的本质我们却所知甚少。要想揭示它的性质,我们必须依赖于天文观测数据。强引力透镜是天体物理和宇宙学研究中最重要的工具和手段之一,已经被广泛的应用。 本文基于强引力透镜的观测数据对宇宙学暗能量模型进行限制。具体来说,本论文分为三章来阐述。第一章是强引力透镜基础知识；第二章是介绍暗能量宇宙学模型；第三章,考虑到透镜星系质量分布理论模型的速度弥散与可观测的恒星速度弥散不同,二者关系与一自由参数fE有关,这一自由参数的存在会对数据拟合产生影响。为了排除自由参数对数值模拟的影响,我们提出了用角直径距离比Dijobs=θEiσ0j2/θEjσ0i2为观测数据,采用蒙特卡罗方法对宇宙学模型进行限制。这里爱因斯坦半径θEi和恒星的速度弥散σoi可以直接从天文观测得到有关数据。文章的最后给出强引力透镜在天文观测中的展望。
[Abstract]:Accurate astronomical observations show that the universe is in a state of accelerating expansion. In recent years, explaining the dark energy of the accelerating expansion of the universe has become a hot issue in cosmology. But we know little about the nature of dark energy. To reveal its nature, we must rely on astronomical observations. As one of the most important tools and means in astrophysics and cosmology, strong gravitational lensing has been widely used. In this paper, the cosmological dark energy model is limited based on the observational data of strong gravitational lensing. Specifically, this paper is divided into three chapters to elaborate. The first chapter is the basic knowledge of strong gravitational lensing, the second chapter is the introduction of dark energy cosmology model. In chapter 3, considering that the velocity dispersion of the theoretical model of lens-galactic mass distribution is different from that of observable stellar velocity dispersion, the relationship between them is related to a free parameter fE, and the existence of this free parameter will have an effect on the data fitting. In order to exclude the influence of free parameters on the numerical simulation, we propose to use Dijobs= 胃 Ei 蟽 0j2/ 胃 Ej 蟽 0i2 as observation data, and use Monte Carlo method to limit the cosmological model. Here the Einstein radius 胃 Ei and the velocity dispersion 蟽 oi of the star can be obtained directly from astronomical observations. Finally, the prospect of strong gravitational lensing in astronomical observation is given.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P159
本文编号：2416224
[Abstract]:Accurate astronomical observations show that the universe is in a state of accelerating expansion. In recent years, explaining the dark energy of the accelerating expansion of the universe has become a hot issue in cosmology. But we know little about the nature of dark energy. To reveal its nature, we must rely on astronomical observations. As one of the most important tools and means in astrophysics and cosmology, strong gravitational lensing has been widely used. In this paper, the cosmological dark energy model is limited based on the observational data of strong gravitational lensing. Specifically, this paper is divided into three chapters to elaborate. The first chapter is the basic knowledge of strong gravitational lensing, the second chapter is the introduction of dark energy cosmology model. In chapter 3, considering that the velocity dispersion of the theoretical model of lens-galactic mass distribution is different from that of observable stellar velocity dispersion, the relationship between them is related to a free parameter fE, and the existence of this free parameter will have an effect on the data fitting. In order to exclude the influence of free parameters on the numerical simulation, we propose to use Dijobs= 胃 Ei 蟽 0j2/ 胃 Ej 蟽 0i2 as observation data, and use Monte Carlo method to limit the cosmological model. Here the Einstein radius 胃 Ei and the velocity dispersion 蟽 oi of the star can be obtained directly from astronomical observations. Finally, the prospect of strong gravitational lensing in astronomical observation is given.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P159
【参考文献】
相关博士学位论文 前2条
1 张敬飞;暗能量宇宙学若干问题的研究[D];大连理工大学;2009年
2 吕剑波;天文观测限制暗能量理论模型的研究[D];大连理工大学;2010年
，本文编号：2416224
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