Soft X-ray excess emission from clusters of galaxies

TL;DR

This paper reviews observational and theoretical research on the soft X-ray excess emission in galaxy clusters, exploring its origins, related phenomena, and implications for understanding the intergalactic medium and cosmic structures.

Contribution

It compiles recent observational data, theoretical models, and future hardware concepts related to the soft X-ray excess in galaxy clusters, highlighting advances in understanding the WHIM and related phenomena.

Findings

Detection of soft X-ray excess in galaxy clusters

Evidence of the warm-hot intergalactic medium (WHIM)

Constraints on cosmic rays and magnetic fields in clusters

Abstract

This is the first meeting specifically devoted to the topic of cluster soft excess and related phenomena. It calls together a group of some 40 scientists, mostly experts in the field, to present their findings on the observational aspects of emission from clusters, signature of the WHIM in the cluster, intergalactic, and local environment, theoretical modeling of the WHIM in cosmological hydrodynamic simulations, theory and observations of cluster cosmic rays, magnetic fields, radio data and the use of the Sunyaev-Zeldovich effect as a means of constraining the important parameters. We are particularly grateful to F.J. Lockman and S.L. Snowden for presenting their latest picture of the cold gas distribution in the interstellar medium, as this affects our ability to model extragalactic EUV and soft X-ray data via Galactic absorption by HI and HeI. Papers given on future hardware concepts to further the spatial and spectral diagnosis of diffuse soft X-ray emission in general are also included.