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Understanding the physical processes that drive the baryon cycle in galaxy ecosystems and their connection with the cosmic environment is a central challenge in modern astrophysics. Dust attenuation serves as a powerful probe for the baryon cycle due to its close association with star formation, interstellar medium (ISM) enrichment, and structural evolution in star-forming galaxies. I will present our discovery of a universal dust attenuation relation, revealing that dust attenuation (IRX = L_ir/L_uv) is determined collectively by IR luminosity, galaxy size, metallicity, and axial ratio, rather than stellar mass alone, for both local and distant star-forming galaxies. In contrast, current hydrodynamic simulations fail to replicate this scaling relation, implying that the simulation of baryonic processes requires significant advancement. We developed a novel model of dust-star geometry, with parameters that depend on metallicity, along with well-established empirical relations, being able to successfully replicate the IRX relation. Additionally, we have investigated the influence of the cosmic environment on galaxy growth by characterizing the properties of galaxies in protoclusters at cosmic noon. We uncovered evidence of links between galaxy growth and large-scale structure formation, including an enrichment of extreme starbursts in the outskirts of protoclusters, boosted merger rates in overdense regions, and the suppression of star formation at the core of protoclusters. Deep spectroscopic surveys will be essential to addressing the cosmic environment’s role in shaping galaxy evolution.
XianZhong Zheng is a research professor at Purple Mountain Observatory, Chinese Academy of Sciences, where he leads a group working on galaxy formation and wide-field surveys. He obtained his Ph.D. in astrophysics from the National Astronomical Observatories in 2002. From 2003 to 2007, he worked at the Observatoire de Paris-Meudon and the Max-Planck Institute for Astronomy (MPIA). In 2007, He joined the Purple Mountain Observatory, supported by the CAS Hundred Talents Program. His research interests focus on observational studies of galaxy formation and evolution. he has made contributions with over 120 published works. Since 2012, he has led a group engaged in the optical and technical design of the 2.5-meter Wide Field Survey Telescope (WFST), , which is dedicated to mapping the northern sky with key science goals on time-domain events, solar system objects, and the structures of the Milky Way and the nearby universe. The construction of WFST, jointly funded by USTC, PMO and Qinghai government, was successfully completed in 2023.