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.
CHEX-MATE: Exploring the kinematical properties of Planck galaxy clusters / Pizzuti, L.; Barrena, R.; Sereno, M.; Streblyanska, A.; Ferragamo, A.; Maurogordato, S.; Cappi, A.; Ettori, S.; Pratt, G. W.; Castignani, G.; Donahue, M.; Eckert, D.; Gastaldello, F.; Gavazzi, R.; Haines, C. P.; Kay, S. T.; Lovisari, L.; Maughan, B. J.; Pointecouteau, E.; Rasia, E.; Radovich, M.; Sayers, J.. - In: ASTRONOMY & ASTROPHYSICS. - ISSN 0004-6361. - 699:(2025). [10.1051/0004-6361/202555417]
CHEX-MATE: Exploring the kinematical properties of Planck galaxy clusters
Ferragamo A.;
2025
Abstract
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.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
