The Hot and Energetic Universe: The evolution of galaxy groups and clusters

TL;DR

This paper discusses how Athena+ will enable groundbreaking X-ray observations of galaxy groups and clusters, shedding light on their formation, evolution, and the interplay of galaxies, black holes, and intergalactic gas.

Contribution

It highlights the potential of Athena+ to study the hot intergalactic gas in galaxy clusters, addressing key open questions about their evolution from redshift 0.5 to 2.5.

Findings

Athena+ will provide high-sensitivity X-ray data on hot gas in galaxy clusters.

The observations will reveal the chemical enrichment and physical properties of intra-cluster gas.

This will improve understanding of galaxy and black hole co-evolution within large-scale structures.

Abstract

Major astrophysical questions related to the formation and evolution of structures, and more specifically of galaxy groups and clusters, will still be open in the coming decade and beyond: what is the interplay of galaxy, supermassive black hole, and intergalactic gas evolution in the most massive objects in the Universe - galaxy groups and clusters? What are the processes driving the evolution of chemical enrichment of the hot diffuse gas in large-scale structures? How and when did the first galaxy groups in the Universe, massive enough to bind more than 10^7 K gas, form? Focussing on the period when groups and clusters assembled (0.5<z<2.5), we show that, due to the continuum and line emission of this hot intergalactic gas at X-ray wavelengths, Athena+, combining high sensitivity with excellent spectral and spatial resolution, will deliver breakthrough observations in view of the aforementioned issues. Indeed, the physical and chemical properties of the hot intra-cluster gas, and their evolution across time, are a key to understand the co-evolution of galaxy and supermassive black hole within their environments.