Related papers: Infant Galaxy Clusters at Low Redshifts?
We determine the age of 1,104 early-type galaxies in eight rich clusters ($z = 0.0046$ to $0.175$) using a new continuum color technique. We find that galaxies in clusters divide into two populations, an old population with a mean age…
Despite the rapid observational progress in the study of young massive star clusters, the formation of globular clusters still remains poorly understood. Yet, it is emerging that globular cluster formation is intimately linked to the…
To understand the evolution of galaxies, we need to know as accurately as possible how many galaxies were present in the Universe at different epochs. Galaxies in the young Universe have hitherto mainly been identified using their expected…
Globular clusters will be present at high redshifts, near the very beginning of the galaxy formation process. Stellar evolution ensures that they will be much more luminous than today. We show that the redshift distribution at nano-Jansky…
Over the past ten years, there has been a revolution in our understanding of massive young stellar clusters in the Galaxy. Initially, there were no known examples having masses $>10^4$, yet we now know that there are at least a half dozen…
Mass and concentration of clusters of galaxies are related and evolving with redshift. We study the properties of a sample of 31 massive galaxy clusters at high redshift, 0.8 < z < 1.5, using weak and strong lensing observations.…
Galaxy clusters are the largest structures in Universe. They are very important as both cosmological probes and astrophysical laboratories. Several methods have been developed to detect galaxy clusters with different techniques (optical,…
Massive galaxies, such as nearby ellipticals, have relatively low number densities, yet they host the majority of the stellar mass in the universe. Understanding their origin is a central problem of galaxy formation. Age dating of stellar…
We have measured the 3.6 micron luminosity and mass evolution of about 1000 galaxies in 32 clusters at 0.2<z<1.25 with a special attention to methodological issues, as emphasized in this proceeding contribution. We find that the luminosity…
An overview of our current understanding of the formation and evolution of star clusters is given, with main emphasis on high-mass clusters. Clusters form deeply embedded within dense clouds of molecular gas. Left-over gas is cleared within…
Understanding the formation history of brightest cluster galaxies is an important topic in galaxy formation. Utilizing the Planck Sunyaev-Zel'dovich cluster catalog, and applying the Ansatz that the most massive halos at one redshift remain…
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…
An ensemble cluster has been formed from a data set comprising a complete magnitude-limited sample of 680 giant galaxies (M(B) < -19) in 8 low-redshift clusters, normalised by the velocity dispersions and virial radii for the early-type…
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…
Although field galaxy studies have begun to probe the universe at z > 1, evidence for galaxy clusters at such redshifts has been sparse. New observations are accumulating rapidly, however, providing new data on the early evolution of…
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…
Star clusters are ideal tracers of star formation activity in systems outside the volume that can be studied using individual, resolved stars. These unresolved clusters span orders of magnitude in brightness and mass, and their formation is…
How stellar clusters disrupt, and over what timescales, is intimately linked with how they form. Here, we review the theory and observations of cluster disruption, both the suggested initial rapid dissolution phase (infant mortality) and…
We present a pedagogical review on the formation and evolution of galaxies in groups, utilizing observational information from the Local Group to galaxies at z~6. The majority of galaxies in the nearby universe are found in groups, and…
The formation environment of stars in massive stellar clusters is similar to the environment of stars forming in galaxies at a redshift of 1 - 3, at the peak star formation rate density of the Universe. As massive clusters are still forming…