Related papers: The Evolution of Spheroidal Galaxies in Different …
The galaxy evolution is believed to be conditioned by the environment. Isolated galaxies or galaxies in poor groups are an excellent laboratory to study evolutionary mechanisms where effects of the environment are minimal. We present new…
New information has recently become available on the fundamental plane for various samples of early-type galaxies with redshift up to 1.3, both in clusters and in the field. This information is reviewed and clues are derived on the…
In view of the extensive evidence of a tight inter-relationship between spheroidal galaxies (and galactic bulges) and massive black holes hosted at their centers, a consistent model must deal jointly with the evolution of the two…
The Fundamental Plane relates the structural properties of early-type galaxies such as its surface brightness and effective radius with its dynamics. The study of its evolution has therefore important implications for models of galaxy…
We measure the diversity of galaxy groups and clusters with mass M>1E13/h Msun, in terms of the star formation history of their galaxy populations, for the purpose of constraining the mass scale at which environmentally-important processes…
To understand the processes that build up galaxies we investigate the stellar structure and gas kinematics of spiral and irregular galaxies out to redshift 1. We target 92 galaxies in four cluster (z = 0.3 & 0.5) fields to study the…
Deep surveys conducted during the past decades have shown that galaxies in the distant universe are generally of more irregular shapes, and are disky in appearance and in their star formation rate, compared to galaxies in similar…
Variations in the photometric parameters of stellar systems as a function of their evolution and the stellar populations comprising them are investigated. A set of seven evolutionary models with an exponential decrease in the star-formation…
Two-dimensional surface photometry derived from Hubble Space Telescope imaging is presented for a sample of 225 early-type galaxies (assumed to be cluster members) in the fields of 9 clusters at redshifts $0.17 < z < 1.21$. The 94 luminous…
We examine in detail the dynamical structure of an elliptical galaxy simulated in the Lambda CDM scenario. The morphology of the galaxy evolves dramatically over time in response to the mode and timing of mass accretion; smooth deposition…
We use new models of stellar population synthesis to estimate the fraction of stars formed during the last major bursts of star formation in E/S0 galaxies in low-redshift clusters ($z\simlt0.4$) from the spectral signatures of…
Massive quiescent galaxies have much smaller physical sizes at high redshift than today. The strong evolution of galaxy size may be caused by progenitor bias, major and minor mergers, adiabatic expansion, and/or renewed star formation, but…
We present galaxy spectroscopic data on a pencil beam of $10.75' \times7.5'$ centered on the X-ray cluster RXJ0054.0-2823 at $z = 0.29$. We study the spectral evolution of galaxies from $z=1$ down to the cluster redshift in a…
Galaxy morphologies in clusters have undergone a remarkable transition over the past several billion years. Distant clusters at $z \sim 0.4$ are filled with small spiral galaxies, many of which are disturbed and show evidence of multiple…
We present a new chemical evolution model for dwarf spheroidal galaxies (dSphs) in the Local Universe. Our main aim is to explain both their observed star formation histories and metallicity distribution functions simultaneously. Applying…
A model is developed for an idealised spherical galaxy evolving from a uniform mass distribution at the epoch of galactic separation until attaining an equilibrium state through gravitational collapse. The final theoretical radial surface…
At z=0, clusters are primarily populated by red, elliptical and massive galaxies, while blue, spiral and lower-mass galaxies are common in low-density environments. Understanding how and when these differences were established is of…
We describe the first results from two observational projects aimed at measuring the amount and spatial distribution of dark matter in distant early-type galaxies (E/S0s) and clusters of galaxies. At the galaxy scale, the Lenses Structure…
We measure the morphology-density relation of galaxies at z=1 across the full three orders of magnitude in projected galaxy density available in low-redshift studies. Our study adopts techniques that are comparable with those applied at…
We investigate the environmental impact of cluster regions on the evolution of nearby S0 galaxies, focusing on their distinct quiescent and star-forming (SF) subpopulations. We select a sample of clusters by crossmatching optical and X-ray…