Main results

We provide the link to the ADS repository, listing the 63 papers (all published in, or submitted to, refereed journals, mostly the Open-Access journal Astronomy & Astrophysics) that contain, in the Acknowledgments, a citation to the code of this PRIN project ("20227RNLY3"). These publications have garnered more than 480 citations as of the end of October 2025. If we exclude papers that contain “XRISM”, “Euclid”, and “eROSITA” in the title, because also covered by other forms of funding, we still have 45 papers cited more than 380 times since 2024.

We highlight here the main achievements of our 2-year project, along with the related outcomes, primarily in the form of peer-reviewed publications. We categorize these achievements according to the four main goals stated in our proposal (“P.a-d”), and describe them in more detail in Section 2.a.

P.a: universal thermodynamic profiles; absolute mass scale and hydrostatic bias

• We developed a new pipeline for spectral extraction and analysis of XMM-Newton data, based on a physically motivated background model and a Bayesian approach using Markov chain Monte Carlo methods (Rossetti et al. 2024). We applied this new method to a subset of 30 galaxy clusters representative of the CHEX-MATE sample and demonstrated that reliable temperature measurements can be obtained up to regions where the source intensity is as low as 20% of the background, while keeping systematic errors below 10%. The spectral results of this analysis are available at the CDS via anonymous ftp and the official website of the CHEX-MATE collaboration.

• We developed a new technique to derive two-dimensional maps of the ICM density and temperature, and applied it to a subsample of 28 CHEX-MATE clusters to characterize the level of inhomogeneities and measure the global and radial scatter in the temperature and density distribution (Lovisari, Ettori et al. 2024).

• We characterized the intracluster gas entropy profiles in a regime where non-gravitational effects are expected to be minimized by studying a subsample of massive CHEX-MATE objects (Riva et al. 2024).

• We measured dynamical masses for 101 CHEX-MATE clusters and validated them with weak-lensing masses and with Planck masses derived from scaling relations (Sereno et al. 2025), and derived cluster mass profiles for 75 clusters using a more sophisticated procedure (MG-MAMPOSST), which recovers the gravitational potential and the anisotropy profiles from line-of-sight velocities and projected positions of galaxy members (Pizzuti, Barrena, Sereno et al. 2025).

• We investigated the effect of baryon presence on the weak-lensing mass bias and its dependence on the galaxy formation recipe (Giocoli et al. 2025).

• We derived and calibrated relations between cluster masses and radio emission in a subsample of CHEX-MATE objects using LoTSS DR2 data (Balboni, Ettori et al. 2025).

• Sereno (2025) showed that the mass distribution of rich haloes evolved self-similarly at least since the Universe was 5.7 Gyr old.

P.b: testing 𝛬CDM predictions (c-M; sparsity; triaxial shape; gas fraction; gravity) 

• We introduced an analysis method for investigating the three-dimensional triaxial shapes of galaxy clusters from CHEX-MATE (Kim, Sayers, Sereno et al. 2024), and assess some possible orientation-related selection bias (Saxena et al. 2025).

• We measured the cluster splashback radius using the AMICO-DR3 sample (Giocoli et al. 2024). 

• We used a constrained hydrodynamical simulation that replicates the Virgo cluster embedded in its large-scale structure to investigate the impact of its local environment on the splashback radius estimate (Lebeau, Ettori et al. 2024).

• We use simulated galaxy clusters from the Three Hundred project to study both the impact of baryons on the sparsity and its astrophysical and cosmological implications (Corasaniti, Richardson, Ettori et al. 2025) and how the baryon or gas fraction can be accurately related to the total mass through either a parabola or a logarithm in the logarithmic plan (Rasia et al. 2025).

• We built and analyzed state-of-the-art simulations to predict these properties in alternative dark matter models, including SIDM and WDM (Ragagnin et al. 2024, Despali et al. 2025).

P.c:  derivation of the Hubble Constant from joint X-ray and millimetre observables

• We corrected the thermal SZ signal for relativistic effects and model X-ray absorption due to Galactic molecular hydrogen (Bourdin et al. 2023).

• We performed a joint XMM-Newton and Planck analysis of 116 CHEX-MATE clusters to measure the ratio between X-ray spectroscopic and SZ-derived temperatures, and quantified the impact of cluster morphology on the Tₓ/TSZ distribution. finding that relaxed clusters show smaller scatter and ratios closer to unity (De Luca et al. 2025, submitted).

• We are using these results to calibrate X-ray/SZ thermodynamic observables, to derive consistent angular diameter distances for the CHEX-MATE sample, and to measure the Hubble constant (H₀), reducing systematic uncertainties in cluster-based cosmological determinations (De Luca et al. 2026, in preparation).

P.d: constraining 𝛬CDM model with a joint analysis of cluster statistics 

• We used the tomographic clustering properties of DR3 clusters to constrain the cosmological parameters (Romanello et al. 2024).

• We built a new cluster sample using the DR4 of KiDS (Maturi et al. 2025).

• We derived new cosmological constraints from the joint modelling of weak-lensing and count measurements, halving the previous uncertainties (Lesci et al. 2025).

• We derived complementary cosmological constraints using the KiDS-Legacy cosmic shear data (Wright et al. 2025).