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We derive ages, metallicities and [alpha/Fe] ratios from the integrated spectra of 23 globular clusters in M31, by employing multivariate fits to two stellar population models. In parallel we analyze spectra of 21 Galactic globular clusters…

The FLAMES survey ``Na-O anti-correlation and HB" uncovered the modern standard for globular clusters (GCs), that is their ubiquitous multiple stellar populations (MPs) distinct by the abundance of proton-capture elements. That survey can…

Solar and Stellar Astrophysics · Physics 2026-03-25 Eugenio Carretta

As shown in previous works, globular clusters can be used to trace the overall structure of the diffuse stellar populations in early type galaxies if the number of clusters per unit stellar mass depends on metallicity. In this paper we…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Juan C. Forte , E. Irene Vega , Favio R. Faifer

It is widely accepted that individual Galactic globular clusters harbor two coeval generations of stars, the first one born with the `standard' alpha-enhanced metal mixture observed in field Halo objects, the second one characterized by an…

Astrophysics of Galaxies · Physics 2012-03-21 Paula Coelho , Susan Percival , Maurizio Salaris

We present the chemical compositions for eight bright giants in the globular cluster NGC 1851. Our analysis reveals large star-to-star abundance variations and correlations of the light elements O, Na, and Al, a feature found in every well…

Astrophysics · Physics 2009-11-13 David Yong , Frank Grundahl

We have studied the chemical composition of NGC 1806, a massive, intermediate-age globular cluster that shows a double main sequence turnoff. We analyzed a sample of high-resolution spectra (secured with FLAMES at the Very Large Telescope)…

Solar and Stellar Astrophysics · Physics 2015-06-22 A. Mucciarelli , E. Dalessandro , F. R. Ferraro , L. Origlia , B. Lanzoni

In this study, we present the chemical abundances of Fe, Mg, Al, Si, and K for a sample of 233 likely member stars of M 54. All the stars were observed with the FLAMES high-resolution multi-object spectrograph mounted at the VLT. Our…

Solar and Stellar Astrophysics · Physics 2026-01-30 D. A. Alvarez Garay , A. Mucciarelli , P. Ventura , M. Bellazzini , S. Covella

The relations between the luminosities $M_{V}$, the metallicities $[Fe/H]$, the Galactocentric radii $R$, and the central concentration indices $c$ of Galactic globular clusters are discussed. It is found that the most luminous clusters…

Astrophysics · Physics 2009-11-07 Sidney van den Bergh

The Small Magellanic Cloud (SMC) is the host of a rich system of globular clusters (GCs) that span a wide age range. The chemical composition of the SMC clusters is still poorly understood, despite their significance to chemical evolution…

Astrophysics of Galaxies · Physics 2023-07-10 A. Mucciarelli , A. Minelli , C. Lardo , D. Massari , M. Bellazzini , D. Romano , L. Origlia , F. R. Ferraro

The analysis of pseudo-colour diagrams, the so-called chromosome maps, of Galactic globular clusters (GCs) permits to classify them into type I and type II clusters. Type II GCs are characterized by an above-the-average complexity of their…

Astrophysics of Galaxies · Physics 2020-04-15 Matteo Simioni , Antonio Aparicio , Giampaolo Piotto

We study the distribution of aluminum abundances among red giants in the peculiar globular cluster NGC 1851. Aluminum abundances were derived from the strong doublet Al I 8772-8773 A measured on intermediate resolution FLAMES spectra of 50…

Astrophysics of Galaxies · Physics 2015-06-05 Eugenio Carretta , Valentina D'Orazi , Raffaele G. Gratton , Sara Lucatello

The abundance of fluorine in a few Galactic globular clusters is known to strongly vary from star-to-star. These unexpected chemical properties are an additional confirmation of the chemical inhomogeneities already found in several GC, and…

Solar and Stellar Astrophysics · Physics 2015-06-16 P. de Laverny , A. Recio-Blanco

Observed mass-to-light ratios (M/L) of metal-rich globular clusters (GCs) disagree with theoretical predictions. This discrepancy is of fundamental importance since stellar population models provide the stellar masses that underpin most of…

NGC 2419 is a peculiar Galactic globular cluster in terms of size/luminosity, and chemical abundance anomalies. Here, we present Str\"omgren $uvby$ photometry of the cluster. Using the gravity- and metallicity-sensitive $c_1$ and $m_1$…

Astrophysics of Galaxies · Physics 2015-10-12 Matthias J. Frank , Andreas Koch , Sofia Feltzing , Nikolay Kacharov , Mark I. Wilkinson , Mike Irwin

Globular clusters (GCs) are important donors to the build-up of the Milky Way (MW) stellar halo, having contributed at the ten percent level over the Galactic history. Stars that originated from the second generation of dissolved or…

We present measurements of ages, metallicities, and [alpha/Fe] ratios for 16 globular clusters (GC) in NGC 147, NGC 185, and NGC 205 and of the central regions of the diffuse galaxy light in NGC 185, and NGC 205. Our results are based on…

Astrophysics · Physics 2009-11-11 M. E. Sharina , V. L. Afanasiev , T. H. Puzia

We present the chemical abundance analysis of 19 upper main-sequence stars of the young open cluster NGC 6250 (log t ~ 7.42 yr). This work is part of a project aimed at setting observational constraints on the theory of atomic diffusion in…

Solar and Stellar Astrophysics · Physics 2017-01-18 A. J. Martin , M. J. Stift , L. Fossati , S. Bagnulo , C. Scalia , F. Leone , B. Smalley

Many scenarios for the origin of the chemical anomalies observed in globular clusters (GCs; i.e., multiple populations) require that GCs were much more massive at birth, up to $10-100\times$, than they are presently. This is invoked in…

Astrophysics of Galaxies · Physics 2015-08-19 Nate Bastian , Carmela Lardo

Globular cluster (GC) systems around galaxies of a vast mass range show remarkably simple scaling relations. The combined mass of all GCs is a constant fraction of the total galaxy mass and the mean metallicity and metallicity dispersion of…

Astrophysics of Galaxies · Physics 2018-08-24 Nick Choksi , Oleg Gnedin , Hui Li