Related papers: omega-Centauri - an Ultra Compact Dwarf Galaxy ?
Nuclear Clusters (NCs) are common stellar systems in the centres of galaxies. Yet, the physical mechanisms involved in their formation are still debated. Using a parsec-resolution hydrodynamical simulation of a dwarf galaxy, we propose an…
With the help of a statistical parameter derived from optical spectra, we show that the current star formation rate of a galaxy, falling into a cluster along a supercluster filament, is likely to undergo a sudden enhancement before the…
Stars in star clusters are thought to form in a single burst from a common progenitor cloud of molecular gas. However, massive, old globular clusters -- with ages greater than 10 billion years and masses of several hundred thousand solar…
Young, massive star clusters are the most notable and significant end products of violent star-forming episodes triggered by galaxy collisions, mergers, and close encounters. Their contribution to the total luminosity induced by such…
In about 40% of the Local Group galaxies star clusters have been detected so far, but the census is still incomplete. The properties of these clusters are briefly reviewed, and the impact of galaxy environment on the evolution and survival…
Stars in globular clusters are generally believed to have all formed at the same time, early in the Galaxy's history. 'Blue stragglers' are stars massive enough that they should have evolved into white dwarfs long ago. Two possible…
We explore the kinematics and star formation history of the Scorpius Centaurus (Sco-Cen) OB association following the initial identification of sequential, linearly aligned chains of clusters. Building upon our characterization of the…
We review observational evidence bearing on the formation of a prototypical large spiral galaxy, the Milky Way. New ground- and space-based studies of globular star clusters and dwarf spheroidal galaxies provide a wealth of information to…
Star cluster formation is a major mode of star formation in the extreme conditions of interacting galaxies and violent starbursts. Young clusters are observed to form in a variety of such galaxies, a substantial number resembling the…
We present a metallicity distribution based on photometry and spectra for 442 omega Cen cluster members that lie at the main sequence turnoff region of the color-magnitude diagram. This distribution is similar to that found for the red…
Nuclear star clusters (NSCs) are the densest stellar systems in the Universe. They can be found at the center of all galaxy types, but tend to favor galaxies of intermediate stellar mass around 10$^9\,$M$_{\odot}$[1, 2]. Currently, two main…
Star clusters are fundamental building blocks of galaxies. Their formation is related to the density and pressure in progenitor molecular clouds and their environmental conditions. To understand better the dynamical processes driving star…
We present the kinematic properties of a tidally disrupted dwarf galaxy in the Milky Way, based on the hypothesis that its central part once contained the most massive Galactic globular cluster, omega Cen. Dynamical evolution of a…
Open clusters (OCs) are infrequent survivors of embedded clusters gestated in molecular clouds. Up to now, little is known about the initial conditions for the formation of OCs. Here, we studied this issue using high-precision astrometric…
Recent exam of large samples of omega Cen giants shows that it shares with mono-metallic globular clusters the presence of the sodium versus oxygen anticorrelation, within each subset of stars with iron content in the range…
Since 2015 there has been a great deal of interest in a supposed new class of galaxy called Ultra Diffuse Galaxies (UDGs). These are large systems with sizes $> 1.5$ kpc and have surface brightness values which are $\mu > 25$ mag…
We numerically investigate dynamical evolution of non-nucleated dwarf elliptical/spiral galaxies (dE) and nucleated ones (dE,Ns) in clusters of galaxies in order to understand the origin of intracluster stellar objects, such as intracluster…
\omega}Centauri ({\omega}Cen) is the most enigmatic Galactic globular cluster (GC), with unmatched chemical complexity. We combine photometric and spectroscopic catalogs to identify its distinct stellar populations and to investigate their…
Globular clusters as $\omega$ Cen and NGC 2808 appear to have a population of very He-rich stars. From a theoretical point of view, one expects the presence of He-rich stars in all globular clusters showing an oxygen-sodium (O-Na)…
In the last decade, a new kind of stellar systems has been established that shows properties in between those of globular clusters (GCs) and early-type dwarf galaxies. These so-called ultra-compact dwarf galaxies (UCDs) have masses in the…