Cosmic Ray Processes in Galactic Ecosystems

Owen ER, Wu K, Inoue Y, Yang HY, Mitchell A (2023)

Publication Type: Journal article, Review article

Publication year: 2023


Book Volume: 11

Article Number: 86

Journal Issue: 4

DOI: 10.3390/galaxies11040086


Galaxy evolution is an important topic, and our physical understanding must be complete to establish a correct picture. This includes a thorough treatment of feedback. The effects of thermal–mechanical and radiative feedback have been widely considered; however, cosmic rays (CRs) are also powerful energy carriers in galactic ecosystems. Resolving the capability of CRs to operate as a feedback agent is therefore essential to advance our understanding of the processes regulating galaxies. The effects of CRs are yet to be fully understood, and their complex multi-channel feedback mechanisms operating across the hierarchy of galaxy structures pose a significant technical challenge. This review examines the role of CRs in galaxies, from the scale of molecular clouds to the circumgalactic medium. An overview of their interaction processes, their implications for galaxy evolution, and their observable signatures is provided and their capability to modify the thermal and hydrodynamic configuration of galactic ecosystems is discussed. We present recent advancements in our understanding of CR processes and interpretation of their signatures, and highlight where technical challenges and unresolved questions persist. We discuss how these may be addressed with upcoming opportunities.

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Owen, E.R., Wu, K., Inoue, Y., Yang, H.Y., & Mitchell, A. (2023). Cosmic Ray Processes in Galactic Ecosystems. Galaxies, 11(4).


Owen, Ellis R., et al. "Cosmic Ray Processes in Galactic Ecosystems." Galaxies 11.4 (2023).

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