Metal enrichment processes

TL;DR

This paper reviews various processes responsible for transporting metals from galaxies to their surroundings, highlighting their roles, efficiencies, and the lack of a single dominant mechanism due to varying conditions.

Contribution

It provides a comprehensive review of observational evidence, simulations, and efficiencies of different metal enrichment processes in galaxy environments.

Findings

All processes can contribute to metal enrichment.

No single process always dominates due to varying efficiencies.

Enrichment processes vary with galaxy and environmental properties.

Abstract

There are many processes that can transport gas from the galaxies to their environment and enrich the environment in this way with metals. These metal enrichment processes have a large influence on the evolution of both the galaxies and their environment. Various processes can contribute to the gas transfer: ram-pressure stripping, galactic winds, AGN outflows, galaxy-galaxy interactions and others. We review their observational evidence, corresponding simulations, their efficiencies, and their time scales as far as they are known to date. It seems that all processes can contribute to the enrichment. There is not a single process that always dominates the enrichment, because the efficiencies of the processes vary strongly with galaxy and environmental properties.