摘要
星际尘埃是银河系的重要组成部分,其分布和性质对于理解银河系的结构、形成和演化具有重要意义.尘埃导致的星际消光和红化现象会改变观测到的天体光度和颜色,对其进行消光改正是评估天体内禀性质的关键步骤.银河系的三维尘埃消光图包含了尘埃分布的空间信息,这对于进行精确的消光改正以及研究尘埃的分布和性质至关重要.然而,描绘银河系中星际消光的三维分布一直是天文学领域中的重要挑战,其困难之处在于需要对大量恒星的消光值和距离值进行精确测量,因此,这一工作的推进依赖于大规模的银河系巡天观测.本文详细总结了当前用于构建银河系三维消光图的各种方法,并根据探测距离从远到近和分辨率从低到高的不同,将现有的消光图分为三类进行深入讨论.同时,简要介绍了在银河系中用于校正天体三维消光的工具.最后对基于银河系三维消光图的尘埃结构研究进行了回顾.尽管当前在消光研究方面已经取得了显著的进步,并且实现了全天范围内的三维消光测量,但我们也认识到,分辨率、精度以及探测距离等方面仍有待进一步地提高.未来的高精度测光巡天项目将提供更高质量、更高精度的数据,这将对深入理解银河系的结构和化学演化起到至关重要的作用.
Interstellar dust,a crucial component of the Milky Way,dramatically shapes our comprehension of the Galactic structure,formation,and evolution.Dust-induced interstellar extinction/reddening modifies our luminosity/color observations of our targets,necessitating accurate extinction/reddening correction to determine their intrinsic properties.The threedimensional(3D)dust extinction map of the Milky Way is an indispensable tool for precise extinction correction and dust distribution research.This paper provides a comprehensive review of current methodologies used to construct the Milky Way 3D extinction map.Existing extinction maps are categorized into three groups based on their detection distance(from far to near)and resolution(from low to high).The first category includes the Milky Way 3D extinction maps with detection distances exceeding 10 kpc,primarily derived from near-IR photometry data.These maps are indispensable for studies of large-scale Milky Way dust distributions,despite the large systematic error in distance measurements and low distance resolution.Post the release of Gaia data,the second category of 3D extinction maps was derived,offering a detection distance of about 4-5 kpc.These maps have become essential tools for performing 3D extinction corrections in Milky Way studies due to their broad sky coverage and high distance accuracy.The third category of 3D extinction maps offers vital data for understanding the distribution of molecular clouds within the Solar neighborhood,with a detection distance of less than 500 pc.Although achieving a distance uncertainty of 1%and higher resolution is challenging,these maps provide crucial data support for studying the fine internal structure of molecular clouds.Additionally,we introduce tools for 3D extinction correction of objects within the Milky Way.Furthermore,we present a review of dust structure studies based on the Galactic 3D extinction map.The distribution of dust in the Milky Way is generally considered to be disk-shaped,akin to the distribution of stars.Various models have been proposed to describe this,showing a range of scale lengths and heights.A recent study proposes that the Galactic dust disk is better fitted by a two-disk model.The distribution of dust within the Galaxy shows evidences of asymmetric distributions and warping.The study also examines mediumscale structures such as spiral arms,inter-arm structures and supershells.The discovery of these structures provides important observational constraints for understanding the origins of the Galactic spiral arms.Finally,we provide comprehensive insights into the smaller structures within molecular clouds,which are integral to understanding interstellar medium distributions,initial conditions and physical mechanisms of star formation,formation of complex organic molecules and prebiotic materials,and the interaction of turbulence and magnetic fields.Despite significant progress in extinction research and the accomplishment of full-sky 3D extinction measurements,we acknowledge the necessity for further advancements in resolution,accuracy,and detection distance.Upcoming high-precision photometric surveys promise to provide high-quality data with improved measurement accuracy,thereby enhancing our understanding of the Galactic structure and chemical evolution.
作者
陈丙秋
张百松
Bingqiu Chen;Baisong Zhang(South-western Institute for Astronomy Research,Yunnan University,Kunming 650500,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2024年第28期4218-4229,共12页
Chinese Science Bulletin
基金
国家自然科学基金(12322304)资助。
关键词
星际介质
尘埃
消光与红化
银河系结构
银盘
instellar medium
dust
extinction and reddening
galactic structure
disk
作者简介
联系人:陈丙秋,E-mail:bchen@ynu.edu.cn。
