【摘要】：在我們的研究中提出了一個(gè)新的統(tǒng)計(jì)方法來(lái)研究COSMOS巡天中的星系對(duì)比例演化,首先我們利用兩星系的投影幾率作為判斷星系對(duì)的標(biāo)準(zhǔn)建立一個(gè)間接的星系對(duì)樣本,然后用在空間上隨機(jī)分布的星系模擬真實(shí)空間的中的投影星系對(duì),并從樣本的結(jié)果中扣除模擬中得到的投影星系對(duì)的結(jié)果。在我們的工作中發(fā)現(xiàn)在rprsc p范圍存在較嚴(yán)重的屏蔽效應(yīng),rsc p的值在不同的紅移段是不一樣的,大致在～15 h-175kpc到～25 h-175kpc之間。我們從樣本中抽取出統(tǒng)計(jì)上投影距離(rp)落在～20 h-175kpc到～30 h-175kpc范圍內(nèi)的星系對(duì)得到一個(gè)星系對(duì)的取樣樣本,從經(jīng)驗(yàn)上避免了屏蔽效應(yīng)在高紅移星系對(duì)統(tǒng)計(jì)中的影響。通過(guò)與鄰近宇宙中的CPG星系對(duì)樣本[1 3]的統(tǒng)計(jì)比較發(fā)現(xiàn)我們?nèi)拥男窍祵?duì)樣本與CPG樣本有相似的rp分布,說(shuō)明我們?nèi)拥男窍祵?duì)樣本是CPG的演化對(duì)應(yīng)體�；趯�(duì)CPG的演化對(duì)應(yīng)體的分析,我們得到一個(gè)星系對(duì)比例的演化關(guān)系(1+z)m,其中m的值為0.93±0.20,它表明星系對(duì)比例隨著紅移的增加有一個(gè)中等快速的增加。同時(shí)我們也發(fā)現(xiàn)運(yùn)用SExtractor軟件得到的空間COSMOS巡天的星系列表中在高紅移處存在較嚴(yán)重的過(guò)度分化,空間的星系目錄在rprsc p范圍得到的星系對(duì)很大一部分是過(guò)度分化的星系。所以我們對(duì)一些早期的研究得到的星系對(duì)比例有快速演化m≈2.2-3.1的結(jié)論提出嚴(yán)重的質(zhì)疑。另外我們的研究發(fā)現(xiàn)孤立的星系對(duì)周?chē)奈锢憝h(huán)境存在一個(gè)比較明顯且復(fù)雜的演化,所以星系對(duì)比例的演化率并不能直接的轉(zhuǎn)化為星系的并合速率,因?yàn)槭艿叫窍祵?duì)周?chē)锢憝h(huán)境的影響,星系對(duì)的演化時(shí)標(biāo)τm可能存在復(fù)雜的演化,在不同的紅移處τm的值很可能不是一致的,星系對(duì)比例的演化轉(zhuǎn)化為星系并合率時(shí)應(yīng)該包含τm在不同紅移段的變化。我們的研究對(duì)以后的高紅移星系對(duì)的研究也提出了一些新的有趣的且重要的問(wèn)題,屏蔽效應(yīng)對(duì)星系對(duì)選擇的主要影響和星系對(duì)周?chē)锢憝h(huán)境對(duì)星系對(duì)演化時(shí)標(biāo)τm的影響。
[Abstract]:In our study, a new statistical method is proposed to study the proportional evolution of galaxy pairs in the COSMOS survey. First, we use the projection probability of the two systems as the criterion for judging the galaxy pair to establish an indirect galaxy pair sample. Then the projected galaxy pairs in real space are simulated by randomly distributed galaxy pairs in space, and the projected galaxy pairs obtained in the simulation are deducted from the sample results. In our work, it is found that there is a serious shielding effect in the range of rprsc p, the value of, rsc p is different in different red shift segments, which is between ~ 15 h-175kpc and ~ 25 h-175kpc. A sampling sample of a galactic pair with a statistical projection distance of ~ 20 h-175kpc to ~ 30 h-175kpc is obtained from the sample, which avoids the influence of shielding effect on the statistics of highly red-shifted galaxy. The sample is selected from the sample and the sampling sample of galaxy pair with statistical projection distance from ~ 20 h-175kpc to ~ 30 h-175kpc is obtained, which avoids the influence of shielding effect on the statistics of highly red-shifted galaxy. Through the statistical comparison with the CPG galaxy pair sample [1 鈮，

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