Fountain-driven gas accretion by the Milky Way

TL;DR

This paper presents hydrodynamic simulations demonstrating how cold galactic fountain clouds facilitate the cooling and accretion of hot coronal gas onto the Milky Way's disc, supporting sustained star formation.

Contribution

It introduces a new simulation-based model showing fountain-driven cooling as a mechanism for gas accretion in star-forming galaxies.

Findings

Fountain clouds induce cooling of hot corona gas.

Gas accretion rate aligns with star formation needs.

Supports fountain-driven accretion as a key process.

Abstract

Accretion of fresh gas at a rate of ~ 1 M_{sun} yr^{-1} is necessary in star-forming disc galaxies, such as the Milky Way, in order to sustain their star-formation rates. In this work we present the results of a new hydrodynamic simulation supporting the scenario in which the gas required for star formation is drawn from the hot corona that surrounds the star-forming disc. In particular, the cooling of this hot gas and its accretion on to the disc are caused by the passage of cold galactic fountain clouds through the corona.