Speaker：

Xiangdong Ji, Hong-Wen Chair Professor, Tsung-Dao Lee Institute, Shanghai Jiao Tong University.

Time：

2026.05.20 16:00-17:30

Venue：

Zhiyuan College(Kuang Piu Building)Lecture Hall, 1st floor

Abstract:

Modern cosmology asserts that the Universe is filled with dark matter, which controls the evolution of the large scale structure and determines the form of the individual galaxies. There are compelling arguments that dark matter particles are a class of weakly-interacting massive particles, or WIMPs, which arise naturally in physics beyond the Standard Model. WIMP searches using various low-energy detectors have been conducted around the globe for more than thirty years, with dramatic improvements in scale and sensitivity. After a brief overview of the field, I will focus on a dark matter experiment, PandaX in the Jinping Underground Lab, Sichuan, China. The PandaX-4T detector used 4-tons ultrapure liquid xenon as the detection target, and reached a record sensitivity of about ~5 events/ton∙year. The current upgrade to a 20-ton experiment will be discussed, along with the prospect of building the world's “ultimate WIMP dark matter detector” in the next decade.

Bio:

Xiangdong Ji, Hong-Wen Chair Professor, Tsung-Dao Lee Institute, Shanghai Jiao Tong University. Dr. Ji received his Ph.D. in 1987 from Drexel University. After two postdoc appointments at Caltech and MIT, he was appointed as an assistant professor at the Center for Theoretical Physics at MIT from 1991 to 1996. From 1996 to 2025, he was a professor at University of Maryland. He has been a professor at Shanghai Jiao Tong University since 2009.

Dr. Ji is a theoretical nuclear as well as an experimental particle physicist. He introduced generalized parton distributions to understand the spin structure of the proton and to map its 3D structure and discovered deeply virtual Compton scattering and related processes to measure them. He also founded the PandaX liquid xenon dark matter experiment in 2009 and served as its spokesperson until 2018.

Dr. Ji has been a Fellow of the American Physical Society since 2000, and was a recipient of the Humboldt research award in Germany in 2014. He was also awarded as a Distinguished Nuclear Physicist by Jefferson Science Association in 2015, and the Herman Feshbach prize in Theoretical Nuclear Physics of the American Physics Society in 2016. He was the recipient of Ruiyuan Science Award by Shanghai Jiao Tong University in 2024.