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We present accurate relative ages for a sample of 55 Galactic globular clusters. The ages have been obtained by measuring the difference between the horizontal branch and the turnoff in two, internally photometrically homogeneous databases.…

Astrophysics · Physics 2009-07-28 F. De Angeli , G. Piotto , S. Cassisi , G. Busso , A. Recio-Blanco , M. Salaris , A. Aparicio , A. Rosenberg

Stars form predominantly in groups usually denoted as clusters or associations. The observed stellar groups display a broad spectrum of masses, sizes and other properties, so it is often assumed that there is no underlying structure in this…

Solar and Stellar Astrophysics · Physics 2016-02-03 S. Pfalzner , H. Kirk , A. Sills , J. S. Urquhart , J. Kauffmann , M. A. Kuhn , A. Bhandare , K. M. Menten

An objective classification of 147 globular clusters in the inner region of the giant elliptical galaxy M87 is carried out with the help of two methods of multivariate analysis. First independent component analysis is used to determine a…

Astrophysics of Galaxies · Physics 2015-11-18 Sukanta Das , Tanuka Chattopadhyay , Emmanuel Davoust

Deep imaging data from the Keck II telescope are employed to study the globular cluster (GC) populations in the cores of six rich Abell clusters. The sample includes A754, A1644, A2124, A2147, A2151, and A2152, and spans the redshift range…

Astrophysics · Physics 2009-10-31 John P. Blakeslee

The connection between a galaxy's total globular cluster system (GCS) mass and its halo mass has been studied for decades and it has been found that galaxies at nearly all observed masses adhere to a linear scaling relation between these…

Astrophysics of Galaxies · Physics 2025-12-10 Veronika Dornan , William E. Harris

Globular clusters (GCs) are spheroidal concentrations typically containing of the order of 10^5 to 10^6, predominantly old, stars. Historically, they have been considered as the closest counterparts of the idealized concept of "simple…

Solar and Stellar Astrophysics · Physics 2015-05-14 A. A. R. Valcarce , M. Catelan

The formation of galaxy clusters in hierarchically clustering universes is investigated by means of high resolution N-body simulations. The simulations are performed using a newly developed multi-mass scheme which combines a PM code with a…

Astrophysics · Physics 2007-05-23 A. Huss , B. Jain , M. Steinmetz

A catalog of Galactic globular clusters has been compiled and used to analyze relations between the chemical and kinematic parameters of the clusters. The catalog contains positions, distances, luminosities, metallicites, and…

Astrophysics of Galaxies · Physics 2019-04-15 V. A. Marsakov , V. V. Koval' , M. L. Gozha

This paper explores if, and to what an extent, the stellar populations of early type galaxies can be traced through the colour distribution of their globular cluster systems. The analysis, based on a galaxy sample from the Virgo ACS data,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Juan C. Forte , E. Irene Vega , Favio R. Faifer

Using a cosmological dark matter simulation of a galaxy-cluster halo, we follow the temporal evolution of its globular cluster population. To mimic the red and blue globular cluster populations, we select at high redshift $(z\sim 1)$ two…

Astrophysics of Galaxies · Physics 2018-02-07 Felipe Ramos-Almendares , Mario G. Abadi , Hernán Muriel , Valeria Coenda

We present the results of a new study of mass segregation in two-component star clusters, based on a large number of numerical N-body simulations using our recently developed dynamical Monte Carlo code. Specifically, we follow the dynamical…

Astrophysics · Physics 2009-11-07 J. M. Fregeau , K. J. Joshi , S. F. Portegies Zwart , F. A. Rasio

The kinematical and spatial properties of the metal-rich globular clusters in the Galaxy ([Fe/H] > -0.8) indicates that these objects do not comprise a homogeneous population. Three subsystems are identified. The highest-mass clusters…

Astrophysics · Physics 2007-05-23 A. Burkert , G. Smith

A comprehensive statistical analysis of the relationship between the chemical and spatially kinematic parameters of the globular clusters of the Galaxy has been performed. The data of the author's compilation catalog contain astrophysical…

Astrophysics of Galaxies · Physics 2020-02-26 V. A. Marsakov , V. V. Koval' , M. L. Gozha

In galaxy clusters, hierarchical assembly predicts the formation of stellar substructures and intracluster light (ICL), a diffuse stellar component tracing the global cluster potential. Because these features are extremely faint,…

The small group of Galactic Globular Clusters (GGC) (Pal 12, Terzan 7, Ruprecht 106, Arp 2) recently discovered to be significantly younger (by ~3-4 Gyr) than the average cluster population of the Galaxy are shown to lie near planes passing…

Astrophysics · Physics 2009-10-28 F. Fusi Pecci , M. Bellazzini , C. Cacciari , F. R. Ferraro

We determine the age of 1,104 early-type galaxies in eight rich clusters ($z = 0.0046$ to $0.175$) using a new continuum color technique. We find that galaxies in clusters divide into two populations, an old population with a mean age…

Astrophysics · Physics 2009-11-13 K. Rakos , J. Schombert , A. Odell

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

Many observable properties of globular clusters (GCs) provide valuable insights for unveiling the hierarchical assembly of their host galaxy. For the Milky Way (MW) in particular, GCs from different accreted satellite galaxies show distinct…

Astrophysics of Galaxies · Physics 2024-04-05 Yingtian Chen , Oleg Y. Gnedin

The core structure of galaxy clusters is fundamentally important. Even though self-gravitating systems have no stable equilibrium state due to their negative heat capacity, numerical simulations find density profiles which are universal in…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Matthias Bartelmann , Marceau Limousin , Massimo Meneghetti , Robert Schmidt

We construct mock galaxy catalogues to analyse clustering properties of a Lambda cold dark matter (LCDM) universe within a cosmological dark matter simulation of sufficient resolution to resolve structure down to the scale of dwarfs. We…

Astrophysics · Physics 2008-11-26 Darren S. Reed , Fabio Governato , Thomas Quinn , Joachim Stadel , George Lake