Understanding the quenching of star formation in the distant Universe

大约100亿年前，最大质量的星系经历了戏剧性的转变，关闭了它们的星星形成，也从盘状星系转变为紧凑的球状系统。我们仍然不明白为什么会发生这种转变，也不明白导致星星形成的关键物理过程。该项目的目的是利用最新的观测数据揭示这一奥秘，重点关注处于转变行为中的过渡星系。非常深的光谱学将提供这些星系在过渡阶段的详细特性（例如它们的金属丰度、星星形成速率、外流速率），而詹姆斯韦伯太空望远镜（JWST）的新红外成像将提供有关这些星系形态转变的前所未有的数据，除了从它们特有的热尘发射中识别出那些包含隐藏的活动星系核（AGN）之外。

Around 10 billion years ago the most massive galaxies underwent a dramatic transformation, switching off their star formation and also changing from disc-like galaxies to compact spheroidal systems. We still do not understand why this transformation occurs, or the key physical process responsible for quenching the star formation. The aim of this project is to use the latest observational data shed light on this mystery, by focusing on the class of transition galaxies caught in the act of transformation. Very deep spectroscopy will provide the detailed properties of these galaxies during their transition phase (e.g. their metallicities, rates of star formation, outflow rates), while new infrared imaging from the James Webb Space Telescope (JWST) will provide unprecedented data on the morphological transformation of these galaxies, in addition to identifying those containing hidden Active Galactic Nuclei (AGN) from their characteristic hot dust emission.