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arXiv · 2505.03708

CHEX-MATE: exploring the kinematical properties of Planck galaxy clusters

Abstract

We analyse the kinematical properties of the CHEX-MATE (Cluster HEritage project with XMM-Newton - Mass Assembly and Thermodynamics at the Endpoint of structure formation) galaxy cluster sample. [...] We derive cluster mass profiles for 75 clusters using the \textsc{MG-MAMPOSSt} procedure, which recovers the gravitational potential and the anisotropy profiles from line-of-sight velocities and projected positions of galaxy members. The standard NFW and the Burkert models with flatter cores than NFW both adequately fit the kinematic data, with only marginal statistical preference for one model over the other. An estimation of the mass bias $(1-B_1) = M^{SZ}_{500}/M^{M}_{500} $ is performed from the comparison with SZ-X-ray-calibrated mass estimates, resulting in a value of $ 0.54 \pm 0.11$ when four evidently disturbed clusters are removed from the sample. We assess the dynamical state of the clusters by inferring the Anderson-Darling coefficient $(A^2)$ and the fraction of galaxies in substructures ($f_\text{sub}$). Except for a few cases, we found relatively low values for $A^2$, suggesting that CHEX-MATE clusters are not too far from relaxation. Moreover, no significant trends emerge among $A^2,\,f_\text{sub}$ and the difference between the log-masses estimated by \textsc{MG-MAMPOSSt} and by SZ-X-ray. We study the concentration-mass relation for the sample; despite the large scatter, we observe signs of an increasing trend for large-mass clusters, in agreement with recent theoretical expectations. Finally, the analysis of radial anisotropy profiles of member galaxies - stacked in five bins of mass and redshift - reveals that orbits tend to be isotropic at the center and more radial towards the edge, as already found in previous studies. A slight trend of increasing radial orbits at $r_{200}$ is observed in clusters with larger velocity dispersion

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BibTeXRIS

Lorenzo Pizzuti, Rafael Barrena, Mauro Sereno, Alina Streblyanska, Antonio Ferragamo, Sophie Maurogordato, Alberto Cappi, Stefano Ettori, Gabriel W. Pratt, Gianluca Castignani, Megan Donahue, Dominique Eckert, Fabio Gastaldello, Raphael Gavazzi, Christopher P. Haines, Scott T. Kay, Lorenzo Lovisari, Ben J. Maughan, Etienne Pointecouteau, Elena Rasia, Mario Radovich, Jack Sayers. 2025-05-06. CHEX-MATE: exploring the kinematical properties of Planck galaxy clusters. https://doi.org/10.1051/0004-6361%2F202555417

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