Related papers: Revisiting the original Morphology-Density Relatio…
It has long been known that the radial density profiles of globular cluster systems (GCSs) in elliptical galaxies vary with the total luminosities of their host galaxies. In order to elucidate the origin of this structural non-homology in…
The scaling relation for early type galaxies in the 6dF galaxy survey does not have the velocity dispersion dependence expected from standard stellar population models. As noted in recent work with SDSS, there seems to be an additional…
We provide fits to the distribution of galaxy luminosity, size, velocity dispersion and stellar mass as a function of concentration index C_r and morphological type in the SDSS. We also quantify how estimates of the fraction of `early' or…
The current formation models for cluster elliptical galaxies which incorporate a mechanism for the metallicity enhancement of massive ellipticals predict a change in the observed slope of the red sequence of ellipticals as a function of…
There are many proposed mechanisms driving the morphological transformation of disk galaxies to elliptical galaxies. In this paper, we determine if the observed transformation in low mass groups can be explained by the merger histories of…
The dwarf galaxies of the Local Group can be separated in three morphological groups: irregular, elliptical and spheroidal. As in the large galaxy clusters, there seems to be a morphology-position relationship: irregular galaxies are…
The last decade of research on elliptical galaxies has produced a wealth of new information concerning both their detailed structure and their global scaling relations. We review the old and new results about isophote shapes and…
Galaxies with different morphological characteristics likely have different evolutionary histories, such that understanding the mechanisms that drive morphological change can provide valuable insights into the galaxy evolution process.…
The most massive elliptical galaxies show a prominent multi-modality in their globular cluster system color distributions. Understanding the mechanisms which lead to multiple globular cluster sub-populations is essential for a complete…
This paper introduces the idea that the general mixing inequality obeyed by evolving stellar phase densities may place useful constraints on the possible history of the over-all galaxy population. We construct simple models for the full…
We derive absorption indices of ellipticals in clusters at z=0.37 from medium-resolution spectroscopy together with kinematical parameters. These galaxies exhibit a relationship between the Mgb linestrength and their internal velocity…
We study the evolution of globular cluster systems (GCS) in elliptical galaxies and explore the dependence of their main properties on the mass and the size of the host galaxy.The dependence of the evolution of the GCS mass function (GCMF),…
We have studied the morphology-density relation and morphology--cluster-centric-radius relation using a volume limited sample (0.05$<z<$0.1, $Mr^*<-$20.5) of the Sloan Digital Sky Survey (SDSS) data. We found there are two characteristic…
Combined HST, X-ray, and ground-based optical studies show that clusters of galaxies are largely "in place" by $z \sim 1$, an epoch when the Universe was less than half its present age. High resolution images show that elliptical, S0, and…
A review of the present observational and theoretical status of elliptical galaxies is presented with the aim to clarify whether the monolithic or the hierarchical, is a more viable scenario for the origin of these structures. We describe…
Here we present HST WFPC2 imaging of 14 kinematically--distinct core ellipticals to examine their globular cluster systems. In particular, we probe the galaxy central regions, for which we might expect to see the strongest signatures of…
We present preliminary results of an extensive study of the fundamental properties of dwarf elliptical galaxies (dEs) in the Coma cluster. Our study will combine HST surface photometry with ground-based UBRIJK photometry and optical…
We compute new population synthesis models of Lick absorption line indices with variable alpha/Fe ratios and use them to derive average ages, metallicities, and alpha/Fe element enhancements for a sample of 126 field and cluster early-type…
We revisit the issue of the recent dynamical evolution of clusters of galaxies using a sample of ACO clusters with z<0.14, which has been selected such that it does not contain clusters with multiple velocity components nor strongly merging…
We use N-body simulations to study the shape of mean cluster density and velocity profiles formed via gravitational instability. The dependence of the final structure on both cosmology and initial density field is examined, using a grid of…