High-energy emission from galaxies: the star-formation/gamma-ray connection

TL;DR

This paper reviews how high-energy gamma-ray emissions from galaxies relate to star formation and AGN activity, highlighting recent detections and future observational prospects with CTA.

Contribution

It summarizes recent progress in understanding galaxy gamma-ray emissions and discusses the potential of upcoming CTA observations to deepen this knowledge.

Findings

Detection of starburst galaxies at GeV and TeV energies.

Gamma-ray emissions linked to star formation and AGN activity.

Future CTA observations will enhance understanding of these processes.

Abstract

The impact of non-thermal processes on the spectral energy distributions of galaxies can be dramatic, but such processes are often neglected in considerations of their structure and evolution. Particle acceleration associated with high mass star formation and AGN activity not only leads to very broad band (radio-\gamma-ray) emission, but may also produce very significant feedback effects on galaxies and their environment. The recent detections of starburst galaxies at GeV and TeV energies suggest that \gamma-ray instruments have now reached the critical level of sensitivity to probe the connection between particle acceleration and star-formation in galaxies. In this paper we will try to summarise this recent progress, put it into a multi-wavelength context and also discuss the prospects for more precise and sensitive \gamma-ray measurements with the upcoming CTA observatory.