M31星族的研究进展  

The Progress of Research on the Stellar Populations of M31

作　　者：刘成[1] 赵刚[1,2] LIU Cheng;ZHAO Gang(Key Lab of Optical Astronomy,National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100012,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院国家天文台光学天文重点实验室,北京100012 [2]中国科学院大学,北京100049

出　　处：《天文学进展》2019年第4期434-454,共21页Progress In Astronomy

基　　金：国家青年科学基金(11703038);中国博士后科学基金(2016M600131);国家天文台青年人才基金;中国科学院天文大科学研究中心LAMOST Fellowship高端用户专项经费

摘　　要：仙女座星系(又称M31)是研究旋涡星系形成和演化的理想实验室。与银河系结构类似,M31包含以下几个基本成分:核、核球、盘和晕等。介绍了对M31各个结构在观测和理论研究方面的最新研究成果:简要回顾了自哈勃空间望远镜升空以来对M31核中结构的观测进展;介绍了核球的两种可能形成机制,并通过观测数据与模型结果的对比,发现M31核球可能同时包含一个经典核球和一个中心类似盒棒的赝核球;总结了盘的星族成分和星际介质的最新观测结果,并据此分别推导出了M31盘上的元素丰度梯度和恒星形成率等。最后,重点总结了晕的可能形成历史,以及球状星团的分布和特征等方面的研究进展。与银河系类似,M31也可能存在内晕和外晕的双结构特征,这表明M31晕与银河系可能有相似的形成历史。此外,通过对晕中潮汐星流的细致研究发现,M31可能有一个比银河系更加复杂的吸积历史。Andromeda,also known as M31,is an ideal libratory to study the formation and evolution of spiral galaxies.The main components of M31 are nucleus,bulge,disk,and halo.They are similar to those of the Milky Way Galaxy.In this review,we introduce the latest results of the main components of M31 from observations,simulations and theoretical studies.We simply summarize the progress of the observations on the structure of nucleus after the Hubble Space Telescope(HST)emission.Two formation mechanisms of the bulge,classical and boxy/peanut-shaped and pseudo bulge,are suggested by comparing simulations and observational data.The results from the observations of stellar populations and interstellar medium in disk are also summarized.The element abundance gradients along radius and star formation rate of the disk could be inferred from those studies.We finally summarize the possible formation history of the halo and the characteristic of globular clusters.Similar to the Galaxy,there might be two overlapping structural components,an inner halo and an outer halo,in the M31 stellar halo.This suggests that our Galaxy and M31 could have a similar formation history.However,evidence from the study of tidal streams implies that M31 may have experienced more accretions than the Milky Way.

关 键 词：星系 M31 晕 盘 星团 恒星 星系形成和演化 

分 类 号：P145.2[天文地球—天体物理]