Princeton University SFIR: Star Formation/ISM Rendezvous

Turbulence is arguably one of the most critical physical processes in galactic disks, playing a key role in the regulation of different phenomena such as star formation, outflows, and gravitational instabilities. High-redshift galactic disks, in particular, exhibit extreme levels of supersonic turbulence, with velocity dispersions ranging from 50 to 150 km/s. Without continuous energy input, this intense turbulence would dissipate rapidly, making it essential to understand the nature and source of its drivers. These drivers not only sustain turbulence but also shape its characteristics, especially the distribution of kinetic energy between compressive and solenoidal modes, which significantly impacts the density structure of the galaxy. A local excess in compressive modes can even assist in local collapse in regions otherwise stabilized against gravitational collapse under classical Toomre framework.

In this talk, I will present an analytical bathtub model for turbulent galactic disks, exploring the role of different turbulence drivers. Additionally, I will demonstrate how giant star-forming clumps can emerge in cosmological simulations, even in regions where the Toomre-Q parameter far exceeds unity, by compressive modes of turbulence. Finally, I will discuss the results of a comparison between observed and simulated clumps using deep learning techniques.