Shanghai Astronomical Observatory Astrophysics Colloquium

Title：Galaxy Formation in the Big Picture of the Cosmic Ecosystem

Speaker：Dr. Enci Wang (USTC)

Time：3:00 pm Apr. 2nd (Thursday)

Tencent Meeting：46822606747 password: 6360

Location: Lecture Hall, 3rd floor

Abstract：Star-forming galaxies continuously accrete gas from their surrounding environment over cosmic time, while stellar feedback simultaneously drives gas outflows and enriches the interstellar and intergalactic medium. The interplay between gas inflow, outflow, and star formation therefore plays a central role in shaping the formation and evolution of galaxies, as well as the key observational relations associated with them. From this perspective, the gas-regulator model can explain a wide range of observed galaxy scaling relations, including the existence and scatter of the star-forming main sequence, the mass–metallicity relation and its dependence on SFR and galaxy size, as well as the HI scaling relations, all arising from time-varying gas inflow during galaxy evolution. In addition, based on the fountain pattern of baryon cycle from simulations and observations, we construct a leaky accretion-disk model to describe the formation of gaseous disks in galaxies. This model quantitatively reproduces the radial gradients of gas-phase metallicity and further suggests that the exponential structure of star-forming disks originates from viscous processes driven by magneto-rotational instability.

CV：In 2011, Enci Wang received the bachelor's degree from the Department of Astronomy, University of Science and Technology of China. In 2016, he obtained the doctorate degree in astrophysics from Shanghai Astronomical Observatory, Chinese Academy of Sciences. From June 2016 to June 2018, he was back to USTC as a postdoctoral researcher. After July 2018, he moved to ETH Zurich and started his second postdoctoral research career. After May 2023, he returned to China and Joined in USTC as a faculty member in department of astronomy.

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