A Multi-Probe Analysis of the 3-D Shapes and Non-Thermal Pressure in the XMM-Heritage Galaxy Clusters

The CHEX-MATE project is a 3 Msec XMM-Heritage program targeting a Planck-SZ–selected sample of 118 galaxy clusters. These clusters represent a well-defined population in the local universe and span the highest-mass regime, making them ideal laboratories for precision cluster astrophysics. 

Our work focuses on developing and applying a multi-probe, three-dimensional triaxial analysis that incorporates Sunyaev–Zel'dovich (SZ) data, X-ray observations, and weak-lensing mass measurements. This approach enables robust constraints on the intrinsic 3D shapes of galaxy clusters and quantifies the non-thermal pressure support in the intracluster medium. The use of a clean, well-characterized sample ensures that the results can be used for both astrophysical insight and cosmological applications.

Our Contributions

We led the development of the CLUMP-3D gas-analysis framework, which combines X-ray imaging and spectroscopy with SZ observations to infer the intrinsic three-dimensional geometry and thermodynamic structure of galaxy clusters. We are extending this framework to combined gas and dark-matter analyses using weak-lensing constraints and to population studies of CHEX-MATE clusters.

Related Publications

• CHEX-MATE: CLUster Multi-Probes in Three Dimensions (CLUMP-3D), II. Combined Gas and Dark Matter Analysis from X-ray, SZE, and WL [ADS] [arXiv]

Gavidia, A., Kim, J., Sayers, J., et al., 2026, A&A, 710, A40

• CHEX-MATE: The impact of triaxiality and orientation on Planck SZ cluster selection and weak lensing mass measurements [ADS] [arXiv]

Saxena, H. et al., including Kim, J., 2025, A&A, 700, A128

• CHEX-MATE: CLUster Multi-Probes in Three Dimensions (CLUMP-3D), I. Gas analysis method using X-ray and Sunyaev–Zel’dovich effect data [ADS] [arXiv]

Kim, J., Sayers, J., Sereno, M., et al., 2024, A&A, 686, A97

Acknowledgments. The "Probing the Structure of the Intracluster Medium Using Multiwavelength Observations and Cosmological Simulations" project was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2019R1A6A1A10073887). The "Illuminating the History of Galaxy Formation and Evolution Through Radio Observations" project was funded by the 2025 KAIST-U.S. Joint Research Collaboration Open Track Project for Early-Career Researchers, supported by the International Office at the Korea Advanced Institute of Science and Technology (KAIST).