Year: 2026
Type: article
Abstract: Context. Galaxy clusters offer powerful insights into the large-scale structure of the Universe and the physics of baryons in hot states. Their scientific exploitation, however, hinges on our ability to accurately measure key thermodynamic properties. Aims. In this work we assess the reliability of current analysis techniques in reconstructing these properties, with a particular focus on samples similar to those observed in the Cluster Heritage project with XMM-Newton (CHEX-MATE). Methods. We developed a suite of dedicated end-to-end simulations of CHEX-MATE-like clusters selected from large-scale hydrodynamical simulations and processed through a newly developed realistic XMM-Newton simulator. We applied a full X-ray data analysis pipeline that includes imaging, spectral fitting, and profile reconstruction to the mock datasets. Results. The gas density profiles can be robustly recovered across a wide radial range when using azimuthal mean surface brightness profiles. Our reconstruction techniques are able to reproduce the intrinsic density profile with the correct scatter, with deviations of at most 10% between 0.1 and 1 × R 500c . The gas mass is reconstructed with better than 1% accuracy. The accurate measurement of temperature profiles is more challenging and possibly subject to biases, particularly in the presence of azimuthal variations and multi-temperature gas along the line of sight, which dominate over projection effects. Conclusions. Our results highlight the need for caution when interpreting cluster temperature measurements and underscore the value of tailored mock observations for understanding observational systematics. These findings also suggest that biases in X-ray temperature measurements alter the interpretation of the thermodynamical state of the intra-cluster medium, an outlook particularly relevant in light of recent low-velocity measurements from the XRISM mission.
Source: Astronomy and Astrophysics
Institutions: University of Geneva, University of Michigan, Trieste Astronomical Observatory, National Institute for Astrophysics, University of Manchester, Excellence Cluster Origins, Max Planck Institute for Astrophysics, Ludwig-Maximilians-Universität München, Institute for Fundamental Physics of the Universe, Osservatorio di Astrofisica e Scienza dello Spazio, University of Rome Tor Vergata, Istituto Nazionale di Fisica Nucleare, Roma Tor Vergata, Sapienza University of Rome, Istituto Nazionale di Fisica Nucleare, Sezione di Bologna, University of Modena and Reggio Emilia, Istituto di Astrofisica Spaziale e Fisica Cosmica di Milano, Center for Astrophysics Harvard & Smithsonian, Centre National de la Recherche Scientifique, Université Paris Cité, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Université Paris-Saclay, Astrophysique, Instrumentation et Modélisation, Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, California Institute of Technology, Universidad Autónoma de Madrid
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,865
OpenAlex ID: W7168509882