Title: Turbulence and Star Formation across Clouds and Galaxies

Speaker: Professor Xunchuan Liu (Leiden University)

Time: 10:00am, July 15, 2026

Location: 5-516, PMO Xianlin Campus

Abstract: Turbulence dominates the early evolutionary phases of interstellar clouds, driving the development of filamentary structures in HI clouds, the formation of transitional clouds, and the mass function of star-forming regions. In this talk, I will share my perspective on how turbulence operates from both theoretical and observational standpoints. Specifically, I will present my recent work utilizing the 100 deg² PPCOS CO survey of the Polaris Flare. Our results demonstrate how pure Kolmogorov turbulence persists from 20 pc down to below 0.1 pc. Within this regime, the density field exhibits multi-fractal structures while the underlying turbulent mode remains unshifted. Additionally, I will discuss how dust couples with HI and CO gas during these early evolutionary stages. I will also outline my view on how dense clumps act as the primary drivers governing star/cluster formation patterns across the Milky Way and the Large Magellanic Clouds (LMCs).