Despite the diversity in the histories of individual galaxies, most of them live slow and die fast. I will firstly introduce a systematic exploration of the galaxy-halo connection, aiming to search for deviations in the spatial distribution of galaxies from the simplest halo model prediction. The null detection paves the way for us to identify the key driver of galaxy quenching within the same halo model framework. I will demonstrate that the halo quenching is the only viable model for reproducing the correct clustering and weak lensing of active vs. quenched galaxies observed in the local Universe. I will then switch gear to the slow lives of active galaxies, which are regulated by the feedback from galactic outflows that continuously enrich their interstellar medium (ISM) and pollute the circumgalactic medium with metals. Intriguingly, the ISM metallicity is closely tied to the star formation rate and stellar mass at the observed epoch, forming a redshift-independent 3D relation, i.e., the fundamental metallicity relation (FMR). While the FMR is widely regarded as the evidence of the galactic baryon cycle being in constant equilibrium, I will use an analytic chemical evolution model (CEM) to show that the 3D relation can naturally emerge without assuming equilibrium. Under the non-equilibrium CEM, the FMR provides a stringent constraint on the physical properties of galactic outflows. Therefore, we argue that different galaxies form stars and enrich their ISM in a non-equilibrium but strikingly coherent fashion across cosmic time, a prediction that can be tested using dwarf galaxies observed by DESI and early galaxies by JWST.
BIO
祖颖 (上海交通大学)2013年在Ohio State University取得天文学博士，之后分别在Carnegie Mellon University宇宙学中心、Ohio State University宇宙学和粒子物理中心进行博士后工作，并于2017年底加入上海交通大学天文系。他的研究内容包括：通过观测类星体光变测量超大质量黑洞质量、利用大型星系巡天揭示暗物质的分布和暗能量的本质、以及使用解析模型结合数值模拟研究星系和星系团的演化。
Host: Song Huang
