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We examine the environmental effects on the photometric properties of galaxies for the rich galaxy cluster ABCG 209 at $z=0.209$. We use archive CFHT optical imaging of a $42\times28\,{\rm arcmin}^{2}$field centred on the cluster to produce a galaxy sample complete to $B=25.0$and $R=24.5$. Both the composite and red sequence galaxy luminosity functions are found to be dependent on the local galaxy surface density, their faint-end slopes becoming shallower with increasing density. We explain this as a combination of the morphology-density relation, and dwarf galaxies being cannibalised and/or disrupted by the cD galaxy and the ICM in the cluster core. The $B-R$colour of the red sequence itself appears 0.02 mag redder for the highest-density regions, indicative of their stellar populations being marginally (<5%) older or (<20%) more metal-rich. This may be due to the galaxies themselves forming earliest in the rarest overdensities marked by rich clusters, or their star-formation being suppressed earliest by the ICM.

We present a detailed analysis of the photometric properties of galaxies in the cluster A 2163B at redshift $z \sim 0.2$. R-, I- and K-band structural parameters, (half light radius ${R_{\rm e}}$, mean surface brightness $\mathrm{\langle \mu \rangle_e}$within ${R_{\rm e}}$and Sersic index ${n}$) are derived for $N \sim 60$galaxies, and are used to study their internal colour gradients. For the first time, we use the slopes of optical-NIR Kormendy relations to study colour gradients as a function of galaxy size, and we derive the Photometric Plane at $z\sim 0.2$in the Kband. Colour gradients are negligible at optical wavelengths, and are negative in the optical-NIR, amounting on average to $\rm -0.48 \pm 0.06$. This result is in agreement with our previous measurements of colour gradients at intermediate redshifts, and imply a metallicity gradient in galaxies of ${\sim}0.2~\rm dex$per radial decade. The analysis of the Kormendy relation suggests that its slope increases from the optical to the NIR, implying that colour gradients do not vary or even do become less steep in more massive galaxies. Such a result is not simply accomodated within a monolithic collapse scenario, while it can be well understood within a hierarchical merging framework. Finally, we derive the first NIR Photometric Plane at $ z \sim 0.2$, accounting for both the correlations on the measurement uncertainties and the selection effects. The Photometric Plane at $ z \sim 0.2$is consistent with that at $z \sim 0$, with an intrinsic scatter significantly smaller than the Kormendy relation but larger than the Fundamental Plane.

We analyse the properties of galaxy populations in the rich Abell cluster ABCG 209 at redshift $z\sim$0.21, on the basis of spectral classification of 102 member galaxies. We take advantage of available structural parameters to study separately the properties of bulge-dominated and disk-dominated galaxies. The star formation histories of the cluster galaxy populations are investigated by using line strengths and the 4000 Å  break, through a comparison to stellar population synthesis models. The dynamical properties of different spectral classes are examined in order to infer the past merging history of ABCG 209. The cluster is characterized by the presence of two components: an old galaxy population, formed very early ($z_{\rm f} \ga $3.5), and a younger ($z_{\rm f} \ga $1.2) population of infalling galaxies. We find evidence of a merger with an infalling group of galaxies occurred 3.5–4.5 Gyr ago. The correlation between the position of the young H$_\delta$-strong galaxies and the X-ray flux shows that the hot intracluster medium triggered a starburst in this galaxy population ~3 Gyr ago.

We derive the luminosity functions in three bands (BVR) for the rich galaxy cluster ABCG?209 at $z=0.21$. The data cover an area of ~78 arcmin2in the Band Rbands, while a mosaic of three pointings was obtained in the Vband, covering an area of approximately 160 arcmin2. The galaxy sample is complete to $B = 22.8$($N {\rm _{gal}} = 339$), $V = 22.5$($N{\rm _{gal}} = 1078$) and $R = 22.0$($N {\rm _{gal}} = 679$). Although the fit of a single Schechter function cannot be rejected in any band, the luminosity functions are better described by a sum of two Schechter functions for bright and faint galaxies, respectively. There is an indication for a presence of a dip in the luminosity functions in the range $V = 20.5{-}21.5$and $R = 20.0{-}21.0$. We find a marked luminosity segregation, in the sense that the number ratio of bright–to–faint galaxies decreases by a factor 4 from the center to outer regions. Our analysis supports the idea that ABCG?209 is an evolved cluster, resulting from the merger of two or more sub–clusters.?

We derive the galaxy luminosity functions in V-, R-, I-, and K-bands of the cluster EIS 0048 at $z \sim 0.64$from data taken at the ESO Very Large Telescope. The data span the restframe wavelength range from UV, which is sensitive to even low rates of star formation, to the NIR, which maps the bulk of the stellar mass. 
By comparing our data and previous results with pure luminosity evolution models, we conclude that bright ($M \leq M^*+1$) cluster galaxies are already assembled at $z \sim 1$and that star formation is almost completed at $z \sim 1.5$.

We present new photometric V-, R- and I-band data for the rich galaxy cluster AC 118 at $z=0.31$. The new photometry covers an area of $8.6\times8.6$arcmin2, corresponding to $2.9\times2.9$Mpc2($H_0=50$km s-1Mpc-1, $q_0=0.5$and $\Lambda = 0$). The data have been collected for a project aimed at studying galaxy evolution through the color-magnitude relation and the fundamental plane. We provide a catalogue including all the sources ($N = 1206$) detected in the cluster field. The galaxy sample is complete to $V=22.8$mag ($N_{\rm gal}=574$), $R=22.3$mag ($N_{\rm gal}=649$) and $I=20.8$mag ($N_{\rm gal}=419$). We give aperture magnitudes within a fixed aperture of 4.4 arcsec and Kron magnitudes. We also give photometric redshifts for 459 sources for which additional U- and K-band photometry is available. We derive and discuss the V- and R-band luminosity functions. The catalogue, which is distributed in electronic form, is intended as a tool for studies in galaxy evolution.