【摘要】：基于CANDELS(Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey)5個深場巡天的多波段測光數(shù)據(jù)和HST WFC3(Hubble Space Telescope Wide Field Camera 3)近紅外(F125W和F160W)高分辨率觀測圖像,利用質(zhì)量限(恒星質(zhì)量M_*10~(10)M_⊙)選取了8002個紅移分布在1z3范圍內(nèi)的星系樣本,并對這些大質(zhì)量星系的形態(tài)和結(jié)構(gòu)性質(zhì)進行了定量分析研究.通過星系形態(tài)的神經(jīng)網(wǎng)絡(luò)分類方法(Conv Nets),將樣本中的星系劃分為4類:橢球星系(SPHeroids,SPH)、早型盤星系(Early-Type Disks,ETD)、晚型盤星系(Late-Type Disks,LTD)和不規(guī)則星系(IRRegulars,IRR).結(jié)果發(fā)現(xiàn)星系的形態(tài)和結(jié)構(gòu)隨紅移發(fā)生演化,在高紅移宇宙星系主要表現(xiàn)出不規(guī)則形態(tài),但到低紅移處橢球和盤主導(dǎo)的哈勃星系形態(tài)序列已經(jīng)形成.在相同紅移區(qū)間內(nèi),不同類型星系的物理尺寸(r_e)中值從大到小的排序是IRR、LTD、ETD和SPH,而對應(yīng)的Sersic指數(shù)(n)中值大小排序卻相反.另外,不同類型星系的re與紅移之間存在明顯的演化關(guān)系,但這樣的現(xiàn)象在平均軸比(b/a)和Sersic指數(shù)與紅移的關(guān)系中并沒有被發(fā)現(xiàn).
[Abstract]:Based on the multiband photometry data of five deep field surveys and HST WFC3 (Hubble Space Telescope wide Field camera 3) Near-Infrared (F125W and F160W) high resolution observation images of CANDELS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey), Using the mass limit (stellar mass) of 10 ~ (10) M _ (298), we selected 8002 samples of galaxies with redshift in the range of 1z3, and quantitatively studied the morphological and structural properties of these massive galaxies. By means of Conv Nets, the galaxies in the sample are divided into four categories: the ellipsoid galaxy (SPH), the Early-Type disk galaxy (ETD), the Late-Type disk galaxy (LTD) and the irregular galaxy (IRR). The results show that the morphology and structure of the galaxies evolve with the redshift, and the main irregular morphology of the Gao Hong shift cosmic galaxies, but the ellipsoid and disk dominated Hubble galaxy shape sequence has been formed at the low redshift. In the same redshift region, the order of median values of physical dimensions from large to small for different types of galaxies is IRR / LTD / ETD and SPHs, whereas the corresponding order of (n) 's median value is opposite. In addition, there is an obvious evolutionary relationship between re and redshift in different types of galaxies, but this phenomenon is not found in the relationship between mean axis ratio (b / a) and Sersic index and redshift.
【作者單位】： 大理大學(xué)天文與科技史研究所;中國科學(xué)院星系與宇宙學(xué)重點實驗室;中國科學(xué)技術(shù)大學(xué)天文學(xué)系;
【基金】：國家自然科學(xué)基金項目(11303002,11225315,11320101002) 中國科學(xué)院戰(zhàn)略性先導(dǎo)科技專項(XDB09000000) 云南省應(yīng)用基礎(chǔ)研究計劃項目(2014FB155)資助
【分類號】：P152
，

本文編號：2128080