What is a globular cluster? An observational perspective

@article{Gratton2019WhatIA,
  title={What is a globular cluster? An observational perspective},
  author={Raffaele Gratton and Angela Bragaglia and Eugenio Carretta and Valentina D’Orazi and Sara Lucatello and Antonio Sollima},
  journal={The Astronomy and Astrophysics Review},
  year={2019},
  volume={27},
  pages={1-136}
}
Globular clusters are large and dense agglomerate of stars. At variance with smaller clusters of stars, they exhibit signs of some chemical evolution. At least for this reason, they are intermediate between open clusters and massive objects such as nuclear clusters or compact galaxies. While some facts are well established, the increasing amount of observational data are revealing a complexity that has so far defied the attempts to interpret the whole data set in a simple scenario. We review… 

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References

SHOWING 1-10 OF 613 REFERENCES

Multiple populations in globular clusters

Recent progress in studies of globular clusters has shown that they are not simple stellar populations, but rather are made up of multiple generations. Evidence stems both from photometry and

Searching for globular cluster-like abundance patterns in young massive clusters - II. Results from the Antennae galaxies

The presence of multiple populations (MPs) with distinctive light element abundances is a widespread phenomenon in clusters older than 6 Gyr. Clusters with masses, luminosities, and sizes comparable

Globular cluster chemistry in fast-rotating dwarf stars belonging to intermediate-age open clusters

The peculiar chemistry observed in multiple populations of Galactic globular clusters is not generally found in other systems such as dwarf galaxies and open clusters, and no model can currently

Properties of stellar generations in globular clusters and relations with global parameters

We revise the scenario of the formation of Galactic globular clusters (GCs) by adding the observed detailed chemical composition of their different stellar generations to the set of their global

Abundance Variations within Globular Clusters

▪ Abstract Abundance variations within globular clusters (GCs), and of GC stars with respect to field stars, are important diagnostics of a variety of physical phenomena, related to the evolution of

Enrichment by supernovae in globular clusters with multiple populations

It is concluded that these globular clusters, like ω Cen, are most probably the relics of more massive primeval dwarf galaxies that merged and disrupted to form the proto-Galaxy.

Multiple Stellar Populations in Globular Clusters

Globular clusters (GCs) exhibit star-to-star variations in specific elements (e.g., He, C, N, O, Na, Al) that bear the hallmark of high-temperature H-burning. These abundance variations can be

The Early Evolution of Globular Clusters: The Case of NGC 2808

Enhancement and spread of helium among globular cluster stars have been recently suggested as a way to explain the horizontal-branch blue tails in those clusters that show a primordial spread in the

The peculiar Na-O anticorrelation of the bulge globular cluster NGC 6440

Context. Galactic globular clusters (GCs) are essential tools for understanding the earliest epoch of the Milky Way, since they are among the oldest objects in the Universe and can be used to trace

Constraining globular cluster formation through studies of young massive clusters - V. ALMA observations of clusters in the Antennae

Some formation scenarios that have been put forward to explain multiple populations within Globular Clusters (GCs) require that the young massive cluster have large reservoirs of cold gas within
...