English

Baryon Cycles in the Biggest Galaxies

Astrophysics of Galaxies 2022-06-23 v2

Abstract

The universe's biggest galaxies have both vast atmospheres and supermassive central black holes. This article reviews how those two components of a large galaxy couple and regulate the galaxy's star formation rate. Models of interactions between a supermassive black hole and the large-scale atmosphere suggest that the energy released as cold gas clouds accrete onto the black hole suspends the atmosphere in a state that is marginally stable to formation of cold clouds. A growing body of observational evidence indicates that many massive galaxies, ranging from the huge central galaxies of galaxy clusters down to our own Milky Way, are close to that marginal state. The gas supply for star formation within a galaxy in such a marginal state is closely tied to the central velocity dispersion (sigma_v) of its stars. We therefore explore the consequences of a model in which energy released during blackhole accretion shuts down star formation when sigma_v exceeds a critical value determined by the galaxy's supernova heating rate.

Keywords

Cite

@article{arxiv.2204.08099,
  title  = {Baryon Cycles in the Biggest Galaxies},
  author = {Megan Donahue and G. Mark Voit},
  journal= {arXiv preprint arXiv:2204.08099},
  year   = {2022}
}

Comments

Updated post page proofs. 272 pages, 68 figures, 666 references, PHYSICS REPORTS invited review. Immediate open access, note: 109 pages in the published page-set version available at https://www.sciencedirect.com/science/article/pii/S0370157322001302?via%3Dihub

R2 v1 2026-06-24T10:50:31.866Z