The GOGREEN survey: Internal dynamics of clusters of galaxies at redshift 0.9–1.4

Abstract

Context. The study of galaxy cluster mass profiles (M(r)) provides constraints on the nature of dark matter and on physical processes affecting the mass distribution. The study of galaxy cluster velocity anisotropy profiles (β(r)) informs the orbits of galaxies in clusters, which are related to their evolution. The combination of mass profiles and velocity anisotropy profiles allows us to determine the pseudo phase-space density profiles (Q(r)); numerical simulations predict that these profiles follow a simple power law in cluster-centric distance. Aims. We determine the mass, velocity anisotropy, and pseudo phase-space density profiles of clusters of galaxies at the highest redshifts investigated in detail to date. Methods. We exploited the combination of the GOGREEN and GCLASS spectroscopic data-sets for 14 clusters with mass M200 ≥ 1014 M⊙ at redshifts 0.9 ≤ z ≤ 1.4. We constructed an ensemble cluster by stacking 581 spectroscopically identified cluster members with stellar mass M⋆ ≥ 109.5 M⊙. We used the MAMPOSSt method to constrain several M(r) and β(r) models, and we then inverted the Jeans equation to determine the ensemble cluster β(r) in a non-parametric way. Finally, we combined the results of the M(r) and β(r) analysis to determine Q(r) for the ensemble cluster. Results. The concentration c200 of the ensemble cluster mass profile is in excellent agreement with predictions from Λ cold dark matter (ΛCDM) cosmological numerical simulations, and with previous determinations for clusters of similar mass and at similar redshifts, obtained from gravitational lensing and X-ray data. We see no significant difference between the total mass density and either the galaxy number density distributions or the stellar mass distribution. Star-forming galaxies are spatially significantly less concentrated than quiescent galaxies. The orbits of cluster galaxies are isotropic near the center and more radial outside. Star-forming galaxies and galaxies of low stellar mass tend to move on more radially elongated orbits than quiescent galaxies and galaxies of high stellar mass. The profile Q(r), determined using either the total mass or the number density profile, is very close to the power-law behavior predicted by numerical simulations. Conclusions. The internal dynamics of clusters at the highest redshift probed in detail to date are very similar to those of lower-redshift clusters, and in excellent agreement with predictions of numerical simulations. The clusters in our sample have already reached a high degree of dynamical relaxation.

Structural and dynamical modeling of WINGS clusters

“…5, top-left panel). Our results support the findings of several studies based on both DM-only and hydrodynamical simulations (Taylor & Navarro 2001;Rasia et al 2004;Dehnen & McLaughlin 2005;Ludlow et al 2010;Navarro et al 2010), and of previous observational studies (Biviano et al 2013;Munari et al 2014;Biviano et al 2016Biviano et al , 2021, and do not support claims against the power-law behavior of Q(r) (Nadler et al 2017). Since our results are based on a stack cluster, we can neither confirm nor reject the numerical result of Schmidt et al (2008) against the universality of Q(r) across different cosmological halos.…”

“…Chae (2014) found that Q(r) is a power law for Coma cluster elliptical galaxies with a slope of 1.93 ± 0.06. On larger scales, Q(r) has been measured in several clusters of galaxies over the redshift range 0.06-1.34, and it has always been found to be similar to, or at least consistent with, the simulation-based expectations, both when Q(r) was defined using the total mass density profile ρ(r) (Biviano et al 2013;Munari, Biviano, & Mamon 2014;Biviano et al 2016Biviano et al , 2021 and when the tracer ν(r) was used instead for tracers of different colors and luminosities (Munari, Biviano, & Mamon 2015;Aguerri et al 2017;Capasso et al 2019).…”

“…The linear β − γ relation was discovered by Hansen & Moore (2006) and Hansen & Stadel (2006) in a variety of simulated gravitating systems, issued from controlled simulations of halo-halo collisions and radial infall, as well as from cosmological simulations. However, the physical origin of the linear β − γ relation is not better elucidated than that of the Q(r) power law, and the relation is not clearly established in real clusters (Biviano et al 2013;Munari et al 2014;Aguerri et al 2017;Biviano et al 2021).…”

The GOGREEN survey: constraining the satellite quenching time-scale in massive clusters at z ≳ 1

“…The remaining three clusters were drawn from the South Pole Telescope (SPT) survey (Brodwin et al 2010;Foley et al 2011;Stalder et al 2013) and were initially detected via their Sunyaev-Zeldovich (Sunyaev & Zeldovich 1970) signature and later spectroscopically confirmed. In Table 2.1, we provide properties of our cluster sample including halo mass (M200) and radial scale (R200) -which are both obtained using the MAMPOSSt method (Mamon et al 2013) as outlined in Biviano et al (2021) -along with redshift and the number of spectroscopic cluster members with M > 10 10 M .…”

“…Properties of our GOGREEN cluster sample, including M 200 , R 200 , cluster redshift, and the number of spectroscopic members (with M > 10 10 M ). The values in the R 200 and M 200 columns were obtained using the MAMPOSSt method(Mamon et al 2013) as outlined inBiviano et al (2021). Details regarding the cluster membership criteria are discussed in Sec.…”