Colloquium talk

Title: The Metal-Enriched Circumgalactic Medium at high-redshift

Speaker: Zheng Cai

Abstract: In this talk, I will present our survey of circumgalactic medium from z=2--6 through both emission and absorption. Using Keck Cosmic Web Imager, combined with the Subaru/HSC, ALMA and VLA, we studied the detailed kinematics of the circumgalactic medium (CGM). Combined with simulations, our observations suggest that CGM could be heavily metal enriched, and the recycled inflow play a vital role in star foramtion at high-redshift. This could be a reason of the rapid formation of the structure found by recent JWST observations.

Bio: Zheng Cai, associate professor at Tsinghua University. Zheng Cai got his PhD degree in astrophysics from the University of Arizona in 2015, and a Hubble fellow at the University of California from 2015 to 2019. From 2019, he joined Tsinghua University. His main research focus include high redshift galaxies, the baryon cycle at high-redshift, and their connection with large-scale environment (e.g., protoclusters). He has discovered the brightest nebulae and revealed gas recycling in the early Universe. He has been awarded XPLORER prize in the year of 2024; Top 10 research advances in the year of 2023. He is also leading the development of next-generation telescopes and survey instruments, including construction of the World's Largest Spectroscopic Survey Telescope (MUST).

Time: 14:00-15:00, 18/Dec, Wednesday
Venue: Room 506 (Large seminar room), Department of Astronomy

You can also access the colloquium via :

https://www.koushare.com/space/329883/live-series/4614