Speaker
Description
The circumgalactic medium (CGM) is the gaseous medium extending far beyond the stellar disk of a galaxy. Recent observations have revealed that it has a rich multiphase structure, i.e., it hosts gas at different densities, temperatures, and ionization states. The complex gas dynamics in the CGM plays a crucial role in establishing gas flows in and out of the galactic disk, regulating star formation in the galaxy. Therefore, understanding the various physical processes in the CGM is crucial to explain the formation and evolution of galaxies. I will cover complementary approaches aimed to understand the multiphase gas physics in models and numerical simulations.
I’ll talk about our works that aim to build a comprehensive understanding of the multiphase CGM through idealized numerical simulations as well as analytic modeling. I’ll talk about survival and growth of cold gas in galactic outflows using our idealized simulations of ‘cloud-crushing’ that considers the downstream expansion of the outflowing wind.
A multiphase CGM leaves its imprint across the electromagnetic spectrum. We are in an era when optical/UV line emission maps of CGM are becoming abundant. So will be X-ray observations with high spectral resolution and radio FRB dispersion measures and thermal and kinetic SZ observations mapping the CGM of both the Milky Way and external galaxies. In this context, I’ll discuss our probabilistic modeling to describe the large-scale (kpc) distribution and statistical properties of the multiphase CGM. Using a suite of multiwavelength synthetic observables, we compare different theoretical models (including ours) with observations. I will highlight why such modeling is timely and how it sets the groundwork that would enable benchmarking models against recent and upcoming observations.
