本文選題：強(qiáng)引力透鏡　切入點(diǎn)：星系團(tuán)　出處：《上海師范大學(xué)》2014年碩士論文

【摘要】：廣義相對(duì)論預(yù)言大質(zhì)量天體會(huì)導(dǎo)致時(shí)空彎曲,并可以使經(jīng)過(guò)它附近的光線偏折到可以觀測(cè)的程度。歷史上,這一預(yù)言已經(jīng)被很多實(shí)驗(yàn)證實(shí)。而本文主要討論的是這種彎曲的一類極端情況,即強(qiáng)引力透鏡現(xiàn)象和它的具體應(yīng)用。一些天文觀測(cè)發(fā)現(xiàn)星系或星系團(tuán)作為透鏡天體能使它們周圍的部分天體發(fā)生明顯的形變,有些甚至可以產(chǎn)生巨大的切向弧。我們可以從這類強(qiáng)引力透鏡現(xiàn)象中獲得很多信息。它們?cè)谔煳纳嫌兄鴱V泛的研究和應(yīng)用。比如強(qiáng)引力透鏡現(xiàn)象可以作為研究星系或星系團(tuán)暗物質(zhì)暈質(zhì)量分布情況的重要工具。具體到本文研究的Abell2219,它是紅移z≈0.22的一個(gè)大質(zhì)量星系團(tuán),具有明顯的引力弧和部分已經(jīng)確定光譜紅移的多重像,可以對(duì)整個(gè)引力透鏡系統(tǒng)提供很強(qiáng)的限制。很適合利用強(qiáng)引力透鏡現(xiàn)象來(lái)模擬分析它的質(zhì)量分布。本文的文章結(jié)構(gòu)概括如下：首先簡(jiǎn)要介紹了引力透鏡的基本原理和常用的質(zhì)量分布模型,并重點(diǎn)分析了PIEMD模型的特點(diǎn)。接著本文又詳細(xì)討論了如何將星系團(tuán)Abell2219作為一個(gè)整體,選擇三個(gè)主要的質(zhì)量團(tuán)塊和這些團(tuán)塊采用的密度輪廓中需要優(yōu)化的模型參數(shù)。本文利用具有可靠的光譜紅移的多重像系統(tǒng)和LENSTOOL軟件,采取蒙特卡洛馬爾科夫鏈的貝葉斯算法,重新估算星系團(tuán)主要質(zhì)量團(tuán)塊的中心速度彌散度等性質(zhì),得到了一個(gè)平均χ2≈6.22的擬合結(jié)果,最后對(duì)這些結(jié)果進(jìn)行了分析和討論。主要結(jié)論有：1)星系團(tuán)的質(zhì)量更多的集中在質(zhì)量團(tuán)塊#1中；2)多重像大多數(shù)位于在團(tuán)塊#1,#2之間使得對(duì)團(tuán)塊#3的模型參數(shù)擬合很難精確。
[Abstract]:The general theory of relativity predicts that mass celestial experience will cause space and time to bend and that light passing through it will deflect to observable levels.Historically, this prediction has been confirmed by many experiments.In this paper, we mainly discuss a kind of extreme case of this kind of bending, that is, the phenomenon of strong gravitational lensing and its concrete application.Some astronomical observations show that galaxies or clusters as lens objects can make some objects around them deform obviously and some even produce huge tangential arcs.We can get a lot of information from this kind of strong gravitational lensing phenomenon.They are widely studied and applied in astronomy.For example, strong gravitational lensing can be used as an important tool to study the mass distribution of dark matter halos in galaxies or clusters.In this paper, Abell2219, a large mass galaxy cluster with redshift z 鈮，

本文編號(hào)：1728033