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We study the star formation histories (SFHs) and mass-weighted ages of 331 UVJ-selected quiescent galaxies in 11 galaxy clusters and in the field at 11 has been driven by different physical processes than those at play at z=0., Comment: accepted Sept 7 2020, MNRAS

We place our sample of 18 Virgo dwarf early-type galaxies (dEs) on the V-K - velocity dispersion, Faber-Jackson, and Fundamental Plane (FP) scaling relations for massive early-type galaxies (Es). We use a generalized velocity dispersion, which includes rotation, to be able to compare the location of both rotationally and pressure supported dEs with those of early and late-type galaxies. We find that dEs seem to bend the Faber-Jackson relation of Es to lower velocity dispersions, being the link between Es and dwarf spheroidal galaxies (dSphs). Regarding the FP relation, we find that dEs are significantly offset with respect to massive hot stellar systems, and re-casting the FP into the so-called kappa-space suggests that this offset is related to dEs having a total mass-to-light ratio higher than Es but still significantly lower than dSph galaxies. Given a stellar mass-to-light ratio based on the measured line indices of dEs, the FP offset allows us to infer that the dark matter fraction within the half light radii of dEs is on average >~ 42% (uncertainties of 17% in the K band and 20% in the V band), fully consistent with an independent estimate in an earlier paper in this series. We also find that dEs in the size-luminosity relation in the near-infrared, like in the optical, are offset from early-type galaxies, but seem to be consistent with late-type galaxies. We thus conclude that the scaling relations show that dEs are different from Es, and that they further strengthen our previous findings that dEs are closer to and likely formed from late-type galaxies., 14 pages, 9 figures, 2 appendixes. Accepted for publication in A&A

International audience; We present a comprehensive analysis of the stellar population properties and morphologies of red-sequence galaxies in 24 clusters and groups from z˜0.75 to z˜0.45. The dataset, consisting of 215 spectra drawn from the ESO Distant Cluster Survey, constitutes the largest spectroscopic sample at these redshifts for which such an analysis has been conducted. Analysis reveals that the evolution of the stellar population properties of red-sequence galaxies depend on their mass: while the properties of the most massive are well described by passive evolution and high-redshift formation, those of the less massive galaxies are consistent with a more extended star-formation history. We show that these scenarios reproduce the index-σ relations and the galaxy colours. The two main results of this work are: (1) the evolution of the line-strength indices for the red-sequence galaxies can be reproduced if 40% of the galaxies with σ< 175 km s-1 entered the red-sequence between z=0.75 to z=0.45, in agreement with the fraction derived in studies of the luminosity functions; and (2) the percentage of red-sequence galaxies exhibiting early-type morphologies (E and S0) decreases by 20% from z=0.75 to z=0.45. This can be understood if the red-sequence becomes more populated at later times with disc galaxies whose star formation has been quenched. We conclude that the processes quenching star formation do not necessarily produce a simultaneous morphological transformation of the galaxies entering the red-sequence. Based on observations obtained at the ESO Very Large Telescope (VLT) as part of the Large Programme 166.A-0162 (the ESO Distant Cluster Survey). Full Table 3 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/499/47

We analyse the cluster color-magnitude relation (CMR) for early-type galaxies in two of the richer clusters in the z ~ 0.9 supercluster system to derive average ages and formation redshifts for the early-type galaxy population. Both clusters were observed with the Advanced Camera for Surveys aboard the {\it Hubble Space Telescope} through the F606W and F814W filters, which brackets the rest-frame 4000 ��break at the cluster redshifts of z\sim 0.9. We fit the zeropoint and slope of the red cluster sequence, and model the scatter about this relation to estimate average galaxy ages and formation redshifts. We find intrinsic scatters of 0.038-0.053 mag in ($V_{606}-I_{814}$) for the E and E+S0 populations, corresponding to average ages of 3.5-3.7 Gyr and formation redshifts z_{f}=2.4-2.6. We find at least one significant difference between the Cl1604+4304 and Cl1604+4321 early-type CMRs. Cl1604+4321, the less X-ray luminous and massive of the two, lacks bright L^* ellipticals. We combine the galaxy samples to fit a composite CMR down to 0.15L^*, and find that the slope of the combined cluster CMR is significantly steeper than for RX J0152.7-1357 but consistent with MS 1054-03, both at similar redshift. The slope of the Cl1604 CMR at the bright end (L > 0.5L^*) is flatter and consistent with the CMR slopes found for other high redshift clusters. We find evidence for increasing scatter with increasing magnitude along the early-type CMR, consistent with a 'downsizing' scenario, indicating younger mean ages with decreasing galaxy mass., replaced to fix bizarre shift in vertical centering, ApJ accepted