The Accretion of Fuel at the Disk-Halo Interface

TL;DR

This paper explores how gas cooling at the disk-halo interface could sustain galaxy fueling, supported by observational evidence, simulations, and cold HI cloud data, addressing the scarcity of cold gas in galaxy halos.

Contribution

It presents new evidence and simulations demonstrating the role of the disk-halo interface in gas recooling and galaxy fueling processes.

Findings

Evidence for net infall of the WIM layer in the Milky Way

Simulation results showing recooling of warm clouds at the disk-halo interface

GALFA HI data revealing small, cold HI clouds as recooling candidates

Abstract

We discuss the support for the cooling of gas directly at the disk-halo interface as a mechanism to continually fuel a galaxy. This may be an important reservoir as there is not enough cold gas observed in galaxy halos and simulations indicate the existing cold clouds will be rapidly destroyed as they move through the surrounding halo medium. We show possible evidence for a net infall of the WIM layer in the Milky Way, simulation results showing the recooling of warm clouds at the disk-halo interface, and GALFA HI data of small, cold HI clouds that could represent this recooling.