We analyzed both HCN J=1-0 and HNC J=1-0 line profiles to study the inflow motions in different evolutionary stages of massive star formation: 54 infrared dark clouds (IRDCs), 69 high-mass protostellar object (HMPOs), and 54 ultra-compact HII regions (UCHIIs). The inflow asymmetry in HCN spectra seems to be prevalent throughout all the three evolutionary phases, with IRDCs showing the largest excess in blue profile. In the case of HNC spectra, the prevalence of blue sources does not appear, excepting for IRDCs. We suggest that this line is not appropriate to trace inflow motion in evolved stages of massive star formation because the abundance of HNC decreases at high temperatures. This result spotlights the importance of considering chemistry in the dynamics study of massive star-forming regions. The fact that the IRDCs show the highest blue excess in both transitions indicates that the most active inflow occurs in the early phase of star formation, i.e., the IRDC phase rather than in the later phases. However, mass is still inflowing onto some UCHIIs. We also found that the absorption dips of the HNC spectra in 6 out of 7 blue sources are red-shifted relative to their systemic velocities. These red-shifted absorption dips may indicate global collapse candidates, although mapping observations with better resolution are needed to examine this feature in more detail.
Identifying signatures of inflow onto face-on galaxies using the Balmer decrement
Columbia University（哥伦比亚大学）；Tsinghua University（清华大学）；Rensselaer Polytechnic Institute（伦斯勒理工学院）；The University of Texas at Dallas（德克萨斯大学达拉斯分校）；York University（约克大学）
Composite Bulges -- V. Detecting signatures of gas inflows in IFU data: The MUSE view of ionised gas kinematics in nearby galaxies
Liverpool John Moores University（利物浦约翰摩尔大学）；University of Nottingham（诺丁汉大学）；Max-Planck-Institut für extraterrestrische Physik（马克斯·普朗克地外物理学研究所）；Universitäts-Sternwarte München（慕尼黑大学天文台）；Durham University（杜伦大学）；Universidade de São Paulo, Instituto de Astronomia, Geofísica e Ciências Atmosféricas（圣保罗大学天文学、地球物理与大气科学研究所）；University of Lancashire（兰开夏大学）；Universidad de La Laguna（拉帕鲁纳大学）
The chemodynamical signature of coherent metal-poor inflow and enriched recycled accretion in the cool circumgalactic medium
Swinburne University of Technology（斯威本科技大学）；The University of Oklahoma（俄克拉荷马大学）；The Pennsylvania State University（宾夕法尼亚州立大学）；New Mexico State University（新墨西哥州立大学）
A Partial Lyman Limit Absorber in the Halo of a Galaxy Pair: A Possible Signature of Gas Inflow
Indian Institute of Space Science and Technology（印度空间科学与技术学院）；Inter-University Centre for Astronomy and Astrophysics (IUCAA)（大学天体物理与天文中心）；The Pennsylvania State University（宾夕法尼亚州立大学）；University of Milano-Bicocca（米兰比可卡大学）
Contrasting evolutionary pathways of fast- and slow-rotating galaxies in the green valley
INAF-Osservatorio Astronomico di Brera（意大利国家天体物理研究所布雷拉天文台）；INAF - Osservatorio Astronomico di Capodimonte（意大利国家天体物理研究所卡波迪蒙特天文台）；Centro de Astrobiología (CAB), CSIC-INTA（西班牙国家科学技术研究委员会-国家航空技术研究所天体生物学中心）
Widespread Inflows Reveal Baryonic Cycling in Star-forming and Quiescent Galaxies
Chinese Academy of Sciences（中国科学院）；Shanghai Astronomical Observatory, Chinese Academy of Sciences（中国科学院上海天文台）；University of Chinese Academy of Sciences（中国科学院大学）；Indian Institute of Astrophysics (IIA)（印度天体物理研究所）；Fudan University（复旦大学）；Peking University（北京大学）；Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学科维理天文与天体物理研究所）；Department of Physics, Fudan University（复旦大学物理系）；Department of Astronomy, School of Physics, Peking University（北京大学物理学院天文学系）；International Centre for Radio Astronomy Research, University of Western Australia（西澳大利亚大学国际无线电天文研究中心）；University of Western Australia（西澳大利亚大学）
Aligned and misaligned metallicity gradients in young stars and star-forming regions in the EAGLE discs
Pontificia Universidad Católica de Chile（智利天主教 Pontificia 大学）；Instituto de Astrofísica, Pontificia Universidad Católica de Chile（智利天主教 Pontificia 大学天体物理研究所）；Centro de Astro-Ingeniería, Pontificia Universidad Católica de Chile（智利天主教 Pontificia 大学天文工程学院）
BLUEPRINT: Blue-dominant Lyman-$α$ emission as evidence of gas inflow in ultra-low-mass galaxies at z = 3
Macquarie University（麦考瑞大学）；Johns Hopkins University（约翰斯·霍普金斯大学）；Swinburne University of Technology（斯威本科技大学）；Università degli Studi di Milano-Bicocca（米兰比可卡大学）；Centro de Astrobiología (CAB), CSIC-INTA（天体生物学中心（CAB），西班牙国家研究委员会-国家航空航天技术研究所）
SMUGGLE-Ring: Evolutionary link between nuclear star cluster and nuclear disk
Université Côte d’Azur, Observatoire de la Côte d’Azur, Laboratoire Lagrange, CNRS（蔚蓝海岸大学、蔚蓝海岸天文台、拉格朗日实验室、法国国家科学研究中心）；Seoul National University（首尔大学）；Università di Bologna（博洛尼亚大学）；INAF, Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所、博洛尼亚空间科学与天体物理观测站）；Massachusetts Institute of Technology（麻省理工学院）；University of California, Riverside（加州大学河滨分校）；Tsinghua University（清华大学）
ATOMS-QUARKS survey: Inflow and infall in massive protocluster G318.049+00.086: Evidence of competitive accretion
Indian Institute of Astrophysics（印度天体物理研究所）；Pondicherry University（本地治里大学）；S.N. Bose National Centre for Basic Sciences（S.N. 玻色基础科学国家中心）；Shanghai Astronomical Observatory, Chinese Academy of Sciences（中国科学院上海天文台）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；Korea Astronomy and Space Science Institute（韩国天文与空间科学研究所）；University of Science and Technology（科学技术大学）；Chinese Academy of Sciences South America Center for Astronomy, National Astronomical Observatories, CAS（中国科学院国家天文台南美天文中心）
DESI Interacting Dwarfs Survey: Multiple Evolutionary Channels of Dwarf Galaxies Driven by Major Dwarf Interactions
Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma（霍默·L·道奇物理与天文学系，俄克拉荷马大学）；Centre for Astrophysics Research, University of Hertfordshire（天体物理学研究中心，赫特福德大学）
Identifying Evolutionary Stages of Molecular Clumps through Unsupervised and Supervised Machine Learning
Institute of Astronomy of the Russian Academy of Sciences（俄罗斯科学院天文研究所）；Ural Federal University named after the first President of Russia B.N.Yeltsin（叶利钦总统乌拉尔联邦大学）；Space Research Institute of the Russian Academy of Sciences（俄罗斯科学院太空研究所）
