A Catalog of Molecular Clumps and Cores with Infall Signatures  

作　　者：Shuling Yu Zhibo Jiang Yang Yang Zhiwei Chen Haoran Feng 于书岭;江治波;杨旸;陈志维;冯浩然(Purple Mountain Observatory,Chinese Academy of Sciences,Nanjing 210023,China;University of Science and Technology of China,Chinese Academy of Sciences,Hefei 230026,China;Center for Astronomy and Space Sciences,Three Gorges University,Yichang 43002,China)

机构地区：[1]Purple Mountain Observatory,Chinese Academy of Sciences,Nanjing 210023,China [2]University of Science and Technology of China,Chinese Academy of Sciences,Hefei 230026,China [3]Center for Astronomy and Space Sciences,Three Gorges University,Yichang 43002,China

出　　处：《Research in Astronomy and Astrophysics》2022年第9期152-175,共24页天文和天体物理学研究（英文版）

基　　金：supported by the National Key R&D Program of China (Grant No. 2017YFA0402702);National Natural Science Foundation of China (NSFC, Grant Nos.11873093 and U2031202);support from the NSFC (Grant No. 11903083)。

摘　　要：The research of infall motion is a common means to study molecular cloud dynamics and the early process of star formation. Many works had been done in-depth research on infall. We searched the literature related to infall study of molecular cloud since 1994, summarized the infall sources identified by the authors. A total of 456 infall sources are cataloged. We classify them into high-mass and low-mass sources, in which the high-mass sources are divided into three evolutionary stages: prestellar, protostellar and H II region. We divide the sources into clumps and cores according to their sizes. The H2 column density values range from 1.21 × 10^(21) to 9.75 × 10^(24) cm^(-2), with a median value of 4.17 × 10^(22) cm^(-2). The H_(2) column densities of high-mass and low-mass sources are significantly separated. The median value of infall velocity for high-mass clumps is 1.12 km s^(-1), and the infall velocities of lowmass cores are virtually all less than 0.5 km s^(-1). There is no obvious difference between different stages of evolution. The mass infall rates of low-mass cores are between 10^(-7) and 10^(-4) M⊙yr^(-1), and those of high-mass clumps are between 10^(-4 )and 10-1 M⊙yr^(-1) with only one exception. We do not find that the mass infall rates vary with evolutionary stages.

关 键 词：stars:formation ISM:molecules ISM:kinematics and dynamics radio lines:ISM 

分 类 号：P152[天文地球—天文学]