Bibcode
Pizzuti, Lorenzo; Barrena, Rafael; Sereno, Mauro; Streblyanska, Alina; Ferragamo, Antonio; Maurogordato, Sophie; Cappi, Alberto; Ettori, Stefano; Pratt, Gabriel W.; Castignani, Gianluca; Donahue, Megan; Eckert, Dominique; Gastaldello, Fabio; Gavazzi, Raphael; Haines, Christopher P.; Kay, Scott T.; Lovisari, Lorenzo; Maughan, Ben J.; Pointecouteau, Etienne; Rasia, Elena; Radovich, Mario; Sayers, Jack
Bibliographical reference
Astronomy and Astrophysics
Advertised on:
7
2025
Journal
Citations
0
Refereed citations
0
Description
We analysed the kinematical properties of the CHEX-MATE galaxy cluster sample. Our study is based on the radial velocities retrieved from the SDSS DR18, DESI, and NED spectroscopic databases and new data obtained with the 10.4 m GTC and ESO-NTT telescopes. We derived cluster mass profiles for 75 clusters using the 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 Navarro–Frenk–White (NFW) model and the Burkert model, with flatter cores than the NFW, both adequately fit the kinematic data, with only a marginal statistical preference for one model over the other. An estimation of the mass bias (1‑B1) = M500SZ/M500M was performed via a comparison with Sunyaev-Zel'dovich–X-ray-calibrated mass estimates, resulting in a value of 0.54 ± 0.11 when four evidently disturbed clusters are removed from the sample. We assessed the dynamical state of the clusters by inferring the Anderson-Darling coefficient (A2) and the fraction of galaxies in substructures (fsub). Except for a few cases, we find relatively low values for A2, which suggests that CHEX-MATE clusters are not too far from relaxation. Moreover, no significant trends emerge between A2 and fsub, nor between the log-masses estimated by MG-MAMPOSST and those based on the Sunyaev–Zel'dovich effect calibrated through X-rays measurements. We studied the concentration–mass relation for the sample; despite the large scatter, we observe signs of an increasing trend for high-mass clusters, in agreement with recent theoretical expectations. Finally, our analysis of the radial anisotropy profiles of member galaxies – stacked in five bins of mass and redshift – reveals that orbits tend to be isotropic at the centre and more radial towards the edge, as found in previous studies. A slight trend of increasing radial orbits at r200 is observed in clusters with larger velocity dispersions. ⋆ Based in part on observations collected at the European Southern Observatory under ESO programmes 0110.A-4192 and 0111.1-0186.