Related papers: A young galaxy cluster in the old Universe
The concept that stars form in the modern era began some 60 years ago with the key observation of expanding OB associations. Now we see that these associations are an intermediate scale in a cascade of hierarchical structures that begins on…
Globular cluster systems exhibit a bewildering variety of characteristics. No single scenario appears to be able to account for the wide range of specific globular cluster frequencies that are observed in galaxies of various types. The…
The total number of globular clusters (GCs) in a galaxy rises continuously with the galaxy luminosity L, while the relative number of galaxies decreases with L following the Schechter function. The product of these two very nonlinear…
Using cosmological N-body simulations of critical (SCDM) and open ($\Omega = 0.3$, OCDM) cold dark matter models, we investigate evolution of cluster galaxies. From our numerical simulation, we construct merging history trees of the…
We combine dissipationless N-body simulations and semi-analytic models of galaxy formation to study the spatial and kinematic distributions of cluster galaxies in a LCDM cosmology. We investigate how the star formation rates, colours and…
We investigate the properties and evolution of star particles in two simulations of isolated spiral galaxies, and two galaxies from cosmological simulations. Unlike previous numerical work, where typically each star particle represents one…
The XMM--LSS project is detecting distant clusters of low mass, quite comparable in mass to the ones in the local universe. This allows a direct comparison of galaxy properties at different redshifts in ``similar'' clusters. We present here…
We analyze the clustering of red and blue galaxies from four samples spanning a redshift range of 0.4<z<2.0 to test the various scenarios by which galaxies evolve onto the red sequence. The data are taken from the UKIDSS Ultra Deep Survey,…
We study the star-formation activity in a sample of $\sim$ 56,000 brightest cluster galaxies (BCGs) at $0.05 < z < 0.42$ using optical and infra-red data from SDSS and WISE. We estimate stellar masses and star-formation rates (SFR) through…
Stellar dynamical model globular clusters are introduced into reconstituted versions of the dark matter halos of the Via-Lactea II (VL-2) simulation to follow the star cluster tidal mass loss and stellar stream formation. The clusters…
The properties of old globular cluster systems in galaxy halos are used to infer quantitative constraints on aspects of generic star (cluster) formation. First, the spatial distribution of globulars in three large galaxies, together with…
One of the most prominent features of galaxy clusters is the presence of a dominant population of massive ellipticals in their cores. Stellar archaeology suggests that these gigantic beasts assembled most of their stars in the early…
We investigated the evolution of clusters of galaxies using self-consistent N-body simulations. We varied the initial model of galaxies and clusters, and studied the dependence of evolution on initial conditions. We found that the growth…
Blue stragglers are anomalously luminous core hydrogen-burning stars formed through mass-transfer in binary/triple systems and stellar collisions. Their physical and evolutionary properties are largely unknown and unconstrained. Here we…
Young stars form on a wide range of scales, producing aggregates and clusters with various degrees of gravitational self-binding. The loose aggregates have a hierarchical structure in both space and time that resembles interstellar…
Diffuse intracluster light (ICL) has now been observed in nearby and in intermediate redshift clusters. Individual intracluster stars have been detected in the Virgo and Coma clusters and the first color-magnitude diagram and velocity…
We present new results of a program to study the detailed morphologies of galaxies in intermediate redshift clusters and hence understand the physical origin of the enhanced star formation in these environments at earlier epochs. Deep, high…
We present clustering measurements and halo masses of star forming galaxies at 0.2 < z < 1.0. After excluding AGN, we construct a sample of 22553 24 {\mu}m sources selected from 8.42 deg^2 of the Spitzer MIPS AGN and Galaxy Evolution Survey…
In previous work on galaxy clusters, several authors reported a discovery of an unusual population of galaxies, which have spiral morphologies, but do not show any star formation activity. These galaxies are called ``passive spirals'', and…
We analyse the evolution of environmental quenching efficiency, the fraction of quenched cluster galaxies that would be star-forming if they were in the field, as a function of redshift in 14 spectroscopically confirmed galaxy clusters with…