Left: phase-space diagram showing 58 XMM2215 cluster galaxies with spectroscopic redshifts inside R₂₀₀. The galaxies with KMOS H-band observations are shown by larger symbols, as indicated in the legend. The dashed large triangle in the lower left-hand corner shows the virialized region, as derived by Rhee et al. (2017) using cosmological hydrodynamic simulations of groups and clusters. Center: spatial distribution of 42 galaxies in the central part of the XMM2215 cluster at R <  0.5R₂₀₀ (symbols like in the left panel). The red filled circle indicates one galaxy with a relatively high [NII]/Hα ratio (but not as high as for the two objects shown in cyan) indicating possible AGN activity. A green star symbol shows the cluster center determined with extended X-ray emission (Stanford et al. 2006). Right: spatial distribution of all 58 cluster galaxies shown in the phase-space diagram (left panel).