EGS场中高红移极亮红外星系的形态与结构

发布时间：2017-12-27 04:24

本文关键词：EGS场中高红移极亮红外星系的形态与结构　出处：《天文学报》2014年06期 　论文类型：期刊论文

【摘要】：通过利用CANDELS-EGS(Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey-Extended Groth Strip)场中HST WFC3(Hubble Space Telescope Wide Field Camera 3)F160W高分辨率的观测图像,研究了9个光谱红极亮红外星系的形态结构特征.发现这些星系的形态表现出多样性(从椭圆到多个亮核或弥散的结构),如:双核,气体桥,双不对称体,不规则或椭圆结构.为了定量地研究这些极亮红外星系的形态,测量了它们在静止光学波段的形态参数(基尼系数G和矩指数M20).与近邻极亮红外星系相比,高红移极亮红外星系的G偏小而M20偏大,表明这些星系的星族分布聚集度小且不对称性大.基于对样本中极亮红外星系2维面亮度轮廓的拟合,得到这些星系的有效半径分布在2.4 kpc到5.8 kpc之间,其平均值是(3.9±1.1)kpc.相比较于近邻相似质量的恒星形成星系来说,高红移极亮红外星系的平均大小要小1到2倍.在类似红移和红外光度条件下,得出的这些结果也与其它文献中给出的结论相一致.
[Abstract]:By using CANDELS-EGS (Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey-Extended Groth Strip WFC3 (Hubble) in HST Space Telescope Wide Field Camera 3) F160W images with high resolution, the configuration of 9 spectral red ultraluminous infrared galaxies. These galaxies that form show diversity (from elliptic to a bright nucleus or dispersion), such as: dual structure, gas bridge, double asymmetric, irregular or ellipse structure. In order to quantitatively study the ulirg form, they still in the optical band shape parameters were measured (Gini coefficient and moment G index M20). Compared with the nearest neighbor ultraluminous infrared galaxies with high redshift ultraluminous infrared Galaxy G is small and M20 is large, indicating that these galaxies population distribution and aggregation degree of asymmetry. In the sample ulirg based on 2 dimensional surface brightness The profile fitting, effective radius distribution of these galaxies in the 2.4 KPC to 5.8 KPC, the average value is (3.9 + 1.1) kpc. compared with the nearest neighbor similar quality star forming galaxies, the average size of high redshift ultraluminous infrared galaxies to 1 to 2 times. In a similar red and infrared photometric conditions and these results are also consistent with other literature given in the conclusion.
【作者单位】：大理学院天文与科技史研究所;中国科学院星系与宇宙学重点实验室;中国科学技术大学天体物理中心;
【基金】：国家自然科学基金项目(11303002,11225315,11320101002) 云南省应用基础研究计划项目(2014FB155) 中国科学院战略性先导科技专项(XDB09000000)资助
【分类号】：P152
【正文快照】： 1引言极亮红外星系(ULtraluminous Infra Red Galaxies,ULIRGs)的红外(IR,8～1000μm)光度分布在1013 L⊙LIR1012L⊙范围内,它们首次被IRAS[1](In-fra Red Astronomical Satellite)红外巡天探测到.在过去的数十年研究工作中,观测已经证明了高红移极亮红外星系是大质量(M*10

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