Massive Compact Galaxies At High Redshift:The Study Of Clustering

Researches in Quiescent Galaxies(QGs)at high redshift have raised a significant interest recently.Rare at both high and low redshift end,but increasing rapidly at z～1-2,peaking at about z-1.5,these galaxies draw widespread attention of astronomers to guess their formation mechanism.Nothing is more famous than the merger model to explain the formation of massive Quiescent Galaxies.However,the most recent work shows that merger model isn’t able to explain the rapid morphology evolution of massive quiescent galaxies at high redshift.Another model that Star Forming Galaxies(SFGs)fade to Quiescent Galaxies has been proposed to explain the rapid number evolution of Quiescent Galaxies at high redshift.In this thesis,we try to combine the data in GOODS-S and COSMOS field to select QGs and SFGs at different redshift bins.Then we derived their physical properties in order to judge the most possible model of the formation of QGs at high redshift.We combine high-resolution Hubble Space Telescope/WFC3 images with multi-wavelength photometry to track the evolution of structure and activity of massive M>1010 M⊙ galaxies at redshifts z = 1-3 in the GOODS-S field of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey(CANDELS)and the COSMOS/UltraVISTA field.We divide our compact samples into compact star forming galaxies(cSFGs)and compact quiescent galaxies(cQGs)and find that cQGs at 1<z<2 are very close to cSFGs at 2<z<3 in morphology,color and clustering properties.Our result approves the model that quenched cSFGs fading into cQGs at z～2,and that cSFGs are likely progenitors of compact,quiescent,massive galaxies at z = 2-3.