We show that the termination of the star formation process by winds from massive stars in protocluster forming clumps imposes dual constraints on the star formation efficiencies (SFEs) and stellar age spreads ($Δτ_{*}$) in stellar clusters. We have considered two main classes of clump models. One class of models in one in which the core formation efficiency (CFE) per unit time and as a consequence the star formation rate (SFR) is constant in time and another class of models in which the CFE per unit time, and as a consequence the SFR, increases with time. Models with an increasing mode of star formation yield shorter age spreads (a few 0.1 Myrs) and typically higher SFEs than models in which star formation is uniform in time. We find that the former models reproduce remarkably well the SFE$-Δτ_{*}$ values of starburst clusters such as NGC 3603 YC and Westerlund 1, while the latter describe better the star formation process in lower density environments such as in the Orion Nebula Cluster. We also show that the SFE and $Δτ_{*}$ of massive clusters are expected to be higher in low metallicity environments. This could be tested with future large extragalactic surveys of stellar clusters. We advocate that placing a stellar cluster on the SFE-$Δτ_{*}$ diagram is a powerful method to distinguish between different stellar clusters formation scenarios such as between generic gravitational instability of a gas cloud/clump or as the result of cloud-cloud collisions. It is also a very useful tool for testing star formation theories and numerical models versus the observations.
RIGEL: Feedback-regulated cloud-scale star formation efficiency in a simulated dwarf galaxy merger
Tsinghua University（清华大学）；University of Bologna（博洛尼亚大学）；INAF, Astrophysics and Space Science Observatory Bologna（意大利国家天体物理研究所博洛尼亚天文与空间科学观测站）；Institute for Advanced Study, Tsinghua University（清华大学高等研究院）；Universität Heidelberg（海德堡大学）；The University of Texas at Dallas（德克萨斯大学达拉斯分校）；York University（约克大学）；Columbia University（哥伦比亚大学）
Bright Galaxies at Cosmic Dawn: A Cloud-Scale Star Formation Model Unifying Variable SFE, IMFs, and Stochasticity
Max Planck Institut für Astrophysik（马克斯·普朗克天体物理学研究所）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；Cosmic Dawn Center (DAWN)（宇宙黎明中心）；Department of Astrophysics, University of Vienna（维也纳大学天体物理系）
Low Star Formation Efficiency in M31: Evidence for a Deficit of Bound Gas
University of Chinese Academy of Sciences（中国科学院大学）；National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）；Max Planck Institute for Astronomy（马克斯·普朗克天文学研究所）；Department of Physics, National Sun Yat-Sen University（国立中山大学物理系）；Center of Astronomy and Gravitation, National Taiwan Normal University（台湾师范大学天文与引力研究中心）；New Cornerstone Science Laboratory, Department of Astronomy, Tsinghua University（清华大学天文系新基石科学实验室）
From short-lived to long-lived clouds: impact of star formation models on giant molecular cloud evolution in simulations of an NGC 300-like galaxy
Yonsei University（延世大学）；Korea Astronomy and Space Science Institute（韩国天体物理与空间科学研究所）；Korea Institute for Advanced Study（韩国高等研究院）；University of Chicago（芝加哥大学）；Centre de Recherche Astrophysique de Lyon UMR5574, Univ Lyon, Univ Lyon1, Ens de Lyon（里昂天体物理研究中心）
Chemo-dynamical reconstruction of Milky Way globular cluster progenitors: Age-metallicity relations and the universality of multiple stellar populations
Dipartimento di Fisica e Astronomia “Augusto Righi”–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天文与空间科学观测站）；Berkeley Center for Cosmological Physics and Department of Physics, University of California, Berkeley（加州大学伯克利分校）；ICC, University of Barcelona（巴塞罗那大学）；ICREA（加泰罗尼亚高级研究学院）
