Related papers: A Model for Clumpy Self-Enrichment in Globular Clu…
The formation of stars with light-element abundance variations in globular clusters and the subsequent dynamical evolution of these multiple populations remains an open question. One of the most widely discussed is the AGB scenario, in…
The process of chemical self-enrichment in stellar systems can be affected by the total mass of the system and the conditions of the large-scale environment. Globular clusters are a special dark matter-free case of chemical evolution, in…
The currently available empirical evidence on the star formation processes in the extreme, high-pressure environments induced by galaxy encounters, mostly based on high-resolution Hubble Space Telescope imaging observations, strongly…
Although globular clusters are generally chemically homogeneous, substantial abundance variations are sometimes seen even among unevolved main sequence stars, especially for the CNO group of elements. Multi-object intermediate-dispersion…
Observed metal abundances in the intracluster medium (ICM) of galaxy groups and clusters, $Z_{ICM}$, exceed what is expected from present-day stellar populations alone. Galaxy clusters are presumed to be near closed-box systems, allowing…
All stars are born in molecular clouds, and most in giant molecular clouds (GMCs), which thus set the star formation activity of galaxies. We first review their observed properties, including measures of mass surface density, Sigma, and…
Globular clusters provide a unique probe of galaxy formation and evolution. Here I briefly summarize the known observational properties of globular cluster systems. One re-occurring theme is that the globular cluster systems of spirals and…
A brief review on globular cluster sub-populations in galaxies, and their constraints on galaxy formation and evolution is given. The metal-poor and metal-rich sub-populations are put in a historical context, and their properties, as known…
One of the conundrums in extragalactic astronomy is the discrepancy in observed metallicity distribution functions (MDFs) between the two prime stellar components of early-type galaxies-globular clusters (GCs) and halo field stars. This is…
We have studied the system of globular clusters (GCs) that formed in other galaxies and eventually accreted onto the Milky Way. Thus, the samples of GCs belonging to different tidal streams, obtained on the basis of the latest data from the…
Hubble Space Telescope ACS/WFC data in (B,I) are used to investigate the globular cluster populations around 6 gE galaxies ~40 Mpc distant. The total comprises a sample of ~8000 high-probability globular clusters. PSF-convolved King-model…
We present a model for the concurrent formation of globular clusters (GCs) and supermassive stars (SMSs, $>10^3\,{\rm M}_\odot$) to address the origin of the HeCNONaMgAl abundance anomalies in GCs. GCs form in converging gas flows and…
Stars in globular clusters (GCs) exhibit a peculiar chemical pattern with strong abundance variations in light elements along with a constant abundance in heavy elements. These abundance anomalies can be explained by a primordial pollution…
Open and globular star clusters have served as benchmarks for the study of stellar evolution due to their supposed nature as simple stellar populations of the same age and metallicity. After a brief review of some of the pioneering work…
In galaxy clusters, hierarchical assembly predicts the formation of stellar substructures and intracluster light (ICL), a diffuse stellar component tracing the global cluster potential. Because these features are extremely faint,…
Evolutionary synthesis models for star clusters of various metallicities including gaseous emission during the lifetime of the ionising stars are used to model star cluster systems comprising two populations: an old metal-poor globular…
We review the multiple population (MP) phenomenon of globular clusters (GCs): i.e., the evidence that GCs typically host groups of stars with different elemental abundances and/or distinct sequences in photometric diagrams. Most Galactic…
Most old globular clusters (GCs) in the Galaxy are observed to have internal chemical abundance spreads in light elements. We discuss a new GC formation scenario based on hierarchical star formation within fractal molecular clouds. In the…
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…
Available X-ray data are collected and organized concerning the iron and gas content of galaxy clusters and groups, together with the optical luminosity, mass and iron abundance of cluster galaxies. Several astrophysical inferences are then…