【摘要】：伽瑪射線暴(簡(jiǎn)稱伽瑪暴)是一種伽瑪射線輻射突然增強(qiáng)的現(xiàn)象,在宇宙中爆發(fā)的方位具有隨機(jī)性,持續(xù)時(shí)間從幾個(gè)毫秒到幾千秒不等。早在1967年被美國(guó)的軍事衛(wèi)星"Vela"所發(fā)現(xiàn),但出于軍事目的,其結(jié)果到1973年才公布于眾。1991年康普頓衛(wèi)星的發(fā)射,人們開始對(duì)伽瑪暴有了基本認(rèn)識(shí)。直到1997年"BeppoSAX"衛(wèi)星的發(fā)射與伽瑪暴余輝的發(fā)現(xiàn),人們才確認(rèn)了伽瑪暴的宇宙學(xué)起源,尤其是光學(xué)余輝中超新星成分的發(fā)現(xiàn),更是直接證論了伽瑪暴與大質(zhì)量恒星的塌縮有關(guān)。2004年11月,美國(guó)航空航天局(NASA)發(fā)射了一顆專門用于研究伽瑪暴的衛(wèi)星"Swift".由于其快速定位能力,使人們能夠迅速作出反應(yīng)并測(cè)定伽瑪暴的紅移。"Swift"最大的貢獻(xiàn)之一便是它為人們提供了大量的伽瑪暴紅移樣本,從此奠定了伽瑪暴作為宇宙學(xué)工具的基礎(chǔ)。 本文以"Swift"衛(wèi)星已知紅移的伽瑪暴樣本為基礎(chǔ),第二至四章將研究伽瑪暴峰值光度與峰值能量之間的相關(guān)性,計(jì)算伽瑪暴的偽紅移,研究伽瑪暴光度函數(shù)的演化效應(yīng),并預(yù)言星族Ⅲ恒星存在的可能。此外,本文第五章通過對(duì)宇宙紅外背景輻射的研究,將進(jìn)一步對(duì)高紅移恒星形成率進(jìn)行限制。 Swift上天后,人們一直致力于研究伽瑪暴光度函數(shù)的演化問題,但始終沒有定論,其中最關(guān)鍵的因素是伽瑪暴紅移樣本的大小。因此,本文第二章主要致力于解決這個(gè)問題。伽瑪暴紅移的測(cè)量無(wú)非是通過余輝或是宿主星系,然而,就目前而言BAT所觸發(fā)的近八百個(gè)暴中只有不到兩百個(gè)暴是有觀測(cè)紅移的。顯然,這對(duì)于研究不同紅移范圍內(nèi)伽瑪暴的光度函數(shù)而言,這個(gè)樣本仍然太小。本文第二章首先通過已知紅移的伽瑪暴樣本,研究它們某些量之間的經(jīng)驗(yàn)關(guān)系。我們發(fā)現(xiàn),伽瑪暴的峰值能量與峰值光度之間存在比較強(qiáng)的相關(guān)性。根據(jù)這個(gè)經(jīng)驗(yàn)關(guān)系,我們估算了近五百個(gè)Swift暴的偽紅移。第三章,通過這個(gè)“擴(kuò)大”的紅移樣本擬合不同紅移范圍內(nèi)的光度分布,我們發(fā)現(xiàn)伽瑪暴光度函數(shù)與紅移之間有明顯的演化效應(yīng)。更讓人意想不到的是,我們發(fā)現(xiàn)伽瑪暴的爆發(fā)率與恒星形成率之間的比例系數(shù)隨紅移增大而減小,這完全顛覆了人們之前的認(rèn)識(shí)。 高紅移恒星形成率一直是天文學(xué)界的研究熱點(diǎn)之一,這也是本文研究的另外一個(gè)重點(diǎn),第四和第五章將主要致力于研究解決這個(gè)問題。本文將從兩個(gè)出發(fā)點(diǎn)出發(fā)：(1)第四章中,首先利用恒星形成率的半解析模型計(jì)算星族Ⅰ/Ⅱ和星族Ⅲ的恒星形成歷史,通過擬合伽瑪暴偽紅移分布,對(duì)高紅移恒星形成率進(jìn)行限制。然后,根據(jù)恒星形成率與CMB光深之間的關(guān)系,進(jìn)一步對(duì)星族Ⅲ恒星形成率進(jìn)行討論研究。然而,令人意想不到的是我們發(fā)現(xiàn)了大量星族Ⅲ恒星伽瑪暴存在于Swfit樣本中的可能,并估計(jì)大概只有1%的星族Ⅲ伽瑪暴能被Swift觀測(cè)到。(2)第五章中,我們先從表象上假設(shè)高紅移恒星形成率的演化形式與低紅移處有類似的情況∝(1+z)a,通過模型計(jì)算,我們可以得到星族Ⅰ/Ⅱ與星族Ⅲ恒星占總恒星形成率的比例。而觀測(cè)上發(fā)現(xiàn)近紅外波段的背景輻射存在一定的超出現(xiàn)象,目前認(rèn)為這些超出部分很可能來(lái)自高紅移的星族Ⅰ/Ⅱ恒星和星族Ⅲ恒星。據(jù)此,我們將高紅移恒星形成率限制在一個(gè)比較平的平臺(tái)范圍內(nèi),冪指數(shù)0(?)α(?)1。
[Abstract]:The gamma-ray burst (gamma-ray) is a phenomenon of a sudden increase in gamma-ray radiation, which is random in the direction of the explosion in the universe, ranging from several milliseconds to several thousand seconds. It was discovered in 1967 by the American military satellite "Vela", but for military purposes, the results were made public in 1973. In 1991, the Compton satellite's launch started to have a basic understanding of the gamma storm. Until the discovery of the emission of the "The BepoSAX" satellite and the afterglow of the gamma storm in 1997, it was confirmed that the cosmological origin of the gamma-storm, especially the discovery of the supernova component in the optical afterglow, was related to the collapse of the gamma-storm and the mass star. In November,2004, NASA has launched a satellite "Swift" dedicated to the study of gamma-storm. As a result of its rapid positioning ability, it is possible to react quickly and to determine the red shift of the gamma storm. One of the most important contributions of the "Swift" is that it provides a large number of gamma-exposure samples to people, laying the foundation for gamma-storm as a cosmic tool. On the basis of the known red-shift gamma-storm samples of the "Swift" satellite, the second to four chapters will study the correlation between the peak luminosity and the peak energy of the gamma-storm, calculate the pseudo-red shift of the gamma-burst, study the evolution effect of the gamma-storm photometric function, and predict the existence of the star-III stars. In addition, Chapter 5 of this paper will further limit the formation rate of the high-red-shift star by studying the radiation of the infrared background of the universe. With Swift, people have been working to study the evolution of the gamma-ray function, but there is no doubt that the most critical factor is the gamma-red-shift sample. Therefore, the second chapter of this article is mainly devoted to solving this problem A problem. The gamma-red-shift measurement is only through the afterglow or the host galaxy. However, only less than two hundred of the nearly eight hundred and most of the's that are currently triggered by BAT are observed. Red shift. It is clear that this sample is still for the photometric function of the gamma-storm in different red-shift ranges The second chapter of this article first, through the known red-shift gamma-storm sample, studies the passage between some of them. We found that there is a strong correlation between the peak energy of the gamma storm and the peak value. The relationship. Based on this empirical relationship, we have estimated nearly 500 Swift storms. Pseudo-red shift. In chapter 3, by fitting the red-shift sample of this "expand" to the photometric distribution in the range of red-shift, we find that there is a clear play between the gamma-gamma function and the red shift. What's more, we find that the ratio of the burst rate of the gamma storm to the star formation rate decreases with the increase of the red shift, which completely subverts the people The high-red-shift star formation rate has been one of the hot spots in the field of astronomy, and this is another key point in this paper. The fourth and the fifth chapter will focus on the research. This paper is based on two starting points: (1) In the fourth chapter, the star formation history of the star group I/ 鈪，

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