Related papers: Multiple populations in Galactic globular clusters…
Recent observations supported by theoretical models have lead to the view that giant and supergiant stars are over abundant, and/or a high metallicity component may be present, in the stellar populations at the centres of active galaxies.…
The formation process of multiple populations in globular clusters is still up for debate. Kinematic differences between the populations are particularly interesting in this respect, because they allow us to distinguish between single-epoch…
We present a long-term project aimed at completing the census of (bright) variable stars in Galactic globular clusters. While our main aim is to obtain a reliable assessment of the populations of RR Lyrae and type II Cepheid stars in the…
We present an overview of observational progress in the study of extragalactic globular cluster systems. Globular clusters turn out to be excellent tracers not only for the star-formation histories in galaxies, but also for kinematics at…
Since the early 1970s, stellar population modelling has been one of the basic tools for understanding the physics of unresolved systems from observation of their integrated light. Models allow us to relate the integrated spectra (or…
Their ubiquity and extreme densities make star clusters probes of prime importance of galaxy evolution. Old globular clusters keep imprints of the physical conditions of their assembly in the early Universe, and younger stellar objects,…
Globular clusters (GCs) are known to host multiple stellar populations showing chemical anomalies in the content of light elements. The origin of such anomalies observed in Galactic GCs is still debated. Here we analyse data compiled from…
In the massive globular cluster NGC 2808, RGB stars form at least five distinct groups in the so-called chromosome map photometric plane, arguably corresponding to different stellar populations. While a human expert can separate the groups…
Galactic globular clusters, which are ancient building blocks of our Galaxy, represent a very interesting family of stellar systems in which some fundamental dynamical processes have taken place on time scales shorter than the age of the…
We review current understanding of the underlying, as opposed to the observed, pulsar population. The observed sample is heavily biased by selection effects, so that surveys see less than 10% of all potentially observable pulsars. We…
The evolution of AGB stars is notoriously complex. The confrontation of AGB population models with observed stellar populations is a useful alternative to the detailed study of individual stars in efforts to converge towards a reliable…
This is a "biased" review because I will show recent evidence on the contribution of globular clusters (GCs) to the halo of our Galaxy seen through the lens of the new paradigm of multiple populations in GCs. I will show a few examples…
Star clusters - open and globulars - experience dynamical evolution on time scales shorter than their age. Consequently, open and globular clusters provide us with unique dynamical laboratories for learning about two-body relaxation, mass…
Over the last decade, the classical definition of Globular Clusters (GCs) as simple stellar populations was revolutionized due to the discovery of "Multiple Populations" (MPs). However, our knowledge of this phenomenon and its…
Globular Clusters (GCs) are known to host distinct stellar populations, characterized by different chemical compositions. Despite extensive research, the origin of these populations remains elusive. According to many formation scenarios,…
Globular cluster ages provide both an important test of models of globular cluster formation and a powerful method to constrain the assembly history of galaxies. Unfortunately, measuring the ages of unresolved old stellar populations has…
A significant number of intermediate age clusters (1-2 Gyr) in the Magellanic Clouds appear to have multiple stellar populations within them, derived from bi-modal or extended main sequence turn offs. If this is interpreted as an age…
The radial distribution of globular clusters in our Galaxy, M31 and M87 is studied and compared with that of halo stars. The globular cluster distributions seem significantly flatter than those of the stars bulge. Assuming this is a…
It is now well-established that most (if not all) ancient globular clusters host multiple popula- tions, that are characterised by distinct chemical features such as helium abundance variations along with N-C and Na-O anti-correlations, at…
The SAURON project will deliver two-dimensional spectroscopic data of a sample of nearby early-type galaxies with unprecedented quality. In this paper, we focus on the mapping of their stellar populations using the SAURON data, and present…