Astronomy & Astrophysics Seminar: The hydrodynamics of Cosmic filaments

Abstract:

Filaments from the cosmic web are responsible for feeding galaxies with most of their gas and supply the majority of gas that ultimately makes stars. I will discuss three different phases of cosmic filament evolution: 1) filament formation, 2) penetration of filaments into halos, and 3) filament-galaxy interactions. During filament formation from cosmic initial perturbation gas falls into filaments and usually shocks. I will examine the conditions for such a shock to be present. Penetration of filaments into halos creates shear flows that may trigger Kelvin-Helmholtz instability between the halo gas and the filaments. I will present a novel analysis about the linear and non-linear evolution of the instability. Finally, filament-galaxy interaction requires the gas to penetrate through galactic magnetic fields before the gas can join the interstellar medium. I will discuss an analytic estimation of this behavior as a function of filament and galactic properties.

Seminar Organizer: Prof. Sara Beck