candels场中z~2星系的形态结构研究
首发时间:2016-05-16
摘要:基于candels(cosmic assembly near-infrared deep extragalactic legacy survey)5个深场巡天的多波段测光数据和hst(hubble space telescope)近红外(f160w)高分辨率观测图像,利用bzk(${m b-z}$和${m z-k}$)双色图技术选取了1586个恒星形成星系(star forminggalaxies, sbzks)和271个被动演化星系(passively evolving galaxies, pbzks),它们对应的红移平均值分别为$1.80pm0.49$和$1.73pm0.38$,并对这些大质量(恒星质量$m_{ st}gtrsim10^{10}~m_{odot}$)星系的形态结构特征进行了研究。在sbzks样本中, 静止光学波段形态呈现出椭圆、盘状和不规则结构特征的源所占比例依次为15%、18%和67%, 而对于pbzks来说, 对应的比例分别是44%、37%和19%。另外,高红移sbzks和pbzks的有效半径($r_{ m e}$)中值分别对应$2.52pm1.37$ kpc和$1.90pm1.02$ kpc, 明显小于近邻同类型相似质量的星系,表明随着红移减小,星系尺寸逐渐变大。
关键词:
for information in english, please click here
morphology and structure of z~2 galaxies in the candels field
abstract:using the multi-band photometry data of all five candels (cosmic assembly near-infrared deep extragalactic legacy survey) fields and the high-resolution hst wfc3 (hubble space telescope wide field camera 3) near-infrared imaging (f160w), we present a quantitative study of morphology and structure ofbzk-selected (two-color ${ m b-z}$ vs. ${m z-k}$ diagram) galaxies. the sample of 1857 bzks including 1586 star-forming galaxies (sbzks) and 271 passively evolving galaxies (pbzks). the mean redshifts of sbzks and pbzks are $1.80pm0.49$ and $1.73pm0.38$, respectively. for the rest-frame optical morphologies of sbzks (pbzks), the fractionsof ellipticals, disks, and irregular galaxies correspond to 15% (44%), 18%(37%), and 67%(19%), respectively.moreover, the median effective radii of sbzks and pbzks, corresponding to $2.52pm1.37$ kpc and $1.90pm1.02$ kpc, respectively. the findings show that the sizes of pbzks (sbzks) are smaller than that of present-day early-type (late-type) galaxies with analogous stellar mass at rest-frame optical wavelength, indicatingthe evolution of high-redshift massive galaxy size with redshift.
keywords:
论文图表:
引用
导出参考文献
no.4687619114497814****
同行评议
共计0人参与
勘误表
candels场中z~2星系的形态结构研究
评论
全部评论0/1000