Galactic Winds and the Role Played by Massive Stars

TL;DR

This paper reviews how massive stars and supernovae drive galactic winds, affecting galaxy evolution and intergalactic medium enrichment, using M82 as a key example.

Contribution

It summarizes physical mechanisms behind galactic winds and analyzes how wind properties depend on galaxy characteristics, highlighting the multiphase nature of these outflows.

Findings

Galactic winds are driven by momentum and energy from massive stars and supernovae.

Wind properties systematically vary with galaxy features.

Galactic winds influence galaxy evolution and intergalactic medium enrichment.

Abstract

Galactic winds from star-forming galaxies play at key role in the evolution of galaxies and the inter-galactic medium. They transport metals out of galaxies, chemically-enriching the inter-galactic medium and modifying the chemical evolution of galaxies. They affect the surrounding inter-stellar and circum-galactic media, thereby influencing the growth of galaxies through gas accretion and star-formation. In this contribution we first summarize the physical mechanisms by which the momentum and energy output from a population of massive stars and associated supernovae can drive galactic winds. We use the proto-typical example of M82 to illustrate the multiphase nature of galactic winds. We then describe how the basic properties of galactic winds are derived from the data, and summarize how the properties of galactic winds vary systematically with the properties of the galaxies that launch them. We conclude with a brief discussion of the broad implications of galactic winds.