The properties of red and massive galaxies at z ~ 2-3

• Main Authors: Meng-Shiou Li, 李孟修
• Other Authors: Tzi-Hong Chiueh
• Format: Others
• Language: en_US
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/20455239727030746622

碩士 === 國立臺灣大學 === 天文物理研究所 === 96 === We use the optical and near-infrared data from GOODSN to study the properties of the red and massive galaxies .This provides the largest sample size to date for galaxies with stellar masses greater than 1010 solar mass . With Hyperz , we have the information of redshifts , stellar mass and rest frame color of our sample galaxies . By plotting the color-mass diagram , we study when the red-sequence first appears and the color bimodality appears . Besides , we also calculate the fraction of the red sequence in different redshift bins to study the evolution of the red sequence , in order to constrain the galaxy formation models . Our results show that the fraction of red sequence galaxies decreases as going to higher redshift . At z < 1 , more than half of the red-sequence galaxies have early-type morphologies , but the fraction decreases to 30 ％ at z ~ 2-3 . Combining this thesis and other researcher’s work , we suggest that three mechanisms may be responsible for the evolution of the red sequence including galaxy transformation ( the blue cloud turned into the red cloud ) , red merger and aging .