Cold flows in haloes and filaments; when they occur, and how they interact with haloes and galaxies  [slides]

Abstract

Virial shocks are expected to form around haloes, as well as around cosmic filaments and sheets. However, due to cooling, gas that accretes onto haloes and filaments does not always heat to the virial temperature, leading to unstable, free falling gas (a.k.a "cold flows"). I will summarize old theoretical results about accretion onto haloes, and present some recent work of gas accretion onto filaments. Once cold flows penetrate through hot virialized haloes, supersonic Kelvin Helmholtz instability occurs, with specific patterns of unstable KH modes. Finally, as cold flows smash into the galaxy, magnetic fields can play a non-trivial role in the way this gas actually mixes with the ISM.