Related papers: Properties of second generation stars in Globular …
Globular clusters (GCs) are the oldest stellar systems in the Milky Way. Long time considered as simple stellar populations, nowadays we recognize their complex star formation history through precise abundance analysis of a variety of…
We obtained FLAMES GIRAFFE+UVES spectra for both first and second-generation red giant branch (RGB) stars in the globular cluster (GC) NGC 362 and used them to derive abundances of 21 atomic species for a sample of 92 stars. The surveyed…
The Horizontal Branch (HB) second parameter of Globular Clusters (GCs) is a major open issue in stellar evolution. Large photometric and spectroscopic databases allow a re-examination of this issue. We derive median and extreme (90% of the…
We present homogeneous abundances for Fe and some of the elements involved in the proton-capture reactions (O, Na, Mg, Al, and Si) for 202 red giants in 17 Galactic globular clusters (GCs) from the analysis of high resolution UVES spectra…
All globular clusters (GCs) studied to date show evidence for internal variation in their light element abundances. These variations have been interpreted as evidence for multiple star formation episodes within GCs, with secondary episodes…
Massive globular clusters (GCs) contain at least two generations of stars with slightly different ages and clearly distinct light elements abundances. The Na-O anticorrelation is the best studied chemical signature of multiple stellar…
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 past decade, the notion that globular clusters (GCs) are composed of coeval stars with homogeneous initial chemical compositions has been challenged by growing evidence that they host an intricate stellar population mix, likely…
A significant fraction of stars in globular clusters (about 70%-85%) exhibit peculiar chemical patterns with strong abundance variations in light elements along with constant abundances in heavy elements. These abundance anomalies can be…
Two generations of stars, G1 and G2, typically populate Galactic globular clusters (GCs). The origin of G2 stars is unclear. We uncover two empirical dependencies between GC characteristics, which can be explained by the formation of G2…
The majority of the inhomogeneities in the chemical composition of Globular Cluster (GC) stars appear due to primordial enrichment. The most studied model today claims that the ejecta of Asymptotic Giant Branch (AGB) stars of high mass…
We present the abundance analysis for a sample of 17 red giant branch stars in the metal-poor globular cluster M28 based on high resolution spectra. This is the first extensive spectroscopic study of this cluster. We derive abundances of O,…
The majority of Galactic globular clusters (GCs) contain multiple stellar populations displaying specific chemical abundance variations. In particular, GCs generally contain a `primordial' population with abundances similar to field stars,…
We numerically investigate abundance properties of the Galactic globular clusters (GCs) by adopting a new ``external pollution'' scenario. In this framework, GCs are assumed to originate in forming low-mass dwarfs embedded in dark matter…
Information on globular clusters (GC) formation mechanisms can be gathered by studying the chemical signature of the multiple populations that compose these stellar systems. In particular, we are investigating the anticorrelations among O,…
We study the formation of multiple populations in globular clusters (GC), under the hypothesis that stars in the second generation formed from the winds of intermediate-mass stars, ejected during the asymptotic giant branch (AGB) phase,…
Long-lived stars in GCs exhibit chemical peculiarities with respect to their halo counterparts. In particular, Na-enriched stars are identified as belonging to a 2d stellar population born from cluster material contaminated by the H-burning…
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…
Homogeneous abundances of light elements, alpha and Fe-group elements from high-resolution FLAMES spectra are presented for 76 red giant stars in M54, a massive globular cluster (GC) lying in the nucleus of the Sagittarius dwarf galaxy. We…
The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters is providing a major breakthrough in our knowledge of Globular Clusters (GCs) and their stellar populations. Among the main results, we discovered that all the…