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Related papers: An Old Cluster in NGC 6822

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We present multi-object spectroscopy of the inner zone of the globular cluster (GC) system associated with the intermediate-age merger remnant NGC 1316. Using the multi-object mode of the GMOS camera, we obtained spectra for 35 GCs. We find…

Astrophysics of Galaxies · Physics 2018-06-04 Leandro A. Sesto , Favio R. Faifer , Analía V. Smith Castelli , Juan C. Forte , Carlos G. Escudero

Hickson Compact Groups (HCGs) constitute an interesting extreme in the range of environments in which galaxies are located, as the space density of galaxies in these small groups are otherwise only found in the centres of much larger…

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 number of known globular clusters in the Galactic bulge has been increasing steadily thanks to different new surveys. The aim of this study is to provide a census of the newly revealed globular clusters in the Galactic bulge, and…

Astrophysics of Galaxies · Physics 2024-08-06 E. Bica , S. Ortolani , B. Barbuy , R. A. P. Oliveira

Using two epochs of HST/WFPC2 images of the metal-rich globular cluster NGC 6528 we derive the proper motions of the stars and use them to separate the stars belonging to NGC 6528 from those of the Galactic bulge. The stellar sequences in…

Astrophysics · Physics 2009-11-07 Sofia Feltzing , Rachel Johnson

Globular Clusters (GCs) in the Milky Way represent the ideal laboratory to establish the age of the oldest stellar populations and to measure the color-magnitude relation of stars. Infrared (IR) photometry of these objects provides a new…

Solar and Stellar Astrophysics · Physics 2018-09-19 Matteo Correnti , Mario Gennaro , Jason S. Kalirai , Roger E. Cohen , Thomas M. Brown

The [Sr/Ba] and [Y/Ba] scatter observed in some galactic halo stars that are very metal-poor stars and in a few individual stars of the oldest known Milky Way globular cluster NGC 6522,have been interpreted as evidence of early enrichment…

Solar and Stellar Astrophysics · Physics 2015-06-22 B. Barbuy , C. Chiappini , E. Cantelli , E. Depagne , M. Pignatari , R. Hirschi , G. Cescutti , S. Ortolani , V. Hill , M. Zoccali , D. Minniti , M. Trevisan , E. Bica , A. Gómez

Spectra of galaxies contain an enormous amount of information about the relative mixture of ages and metallicities of constituent stars. We present a comprehensive study designed to extract the maximum information from spectra of data…

Astrophysics · Physics 2008-11-26 Marsha J. Wolf , Niv Drory , Karl Gebhardt , Gary J. Hill

In the framework of a project aiming at deriving in a homogeneous way the properties (age, distance, reddening and detailed chemical abundances) of a large sample of old open clusters, we present here the metal abundance and the abundance…

Astrophysics · Physics 2009-11-13 Eugenio Carretta , Angela Bragaglia , Raffaele Gratton

We present chemical abundances for 17 elements in a sample of 11 red giant branch stars in NGC 6362 from UVES spectra. NGC 6362 is one of the least massive globulars where multiple populations have been detected, yet its detailed chemical…

Solar and Stellar Astrophysics · Physics 2017-04-12 D. Massari , A. Mucciarelli , E. Dalessandro , M. Bellazzini , S. Cassisi , G. Fiorentino , R. A. Ibata , C. Lardo , M. Salaris

We present new evolutionary stellar models suitable for old Population I clusters, discussing both the consequences of the most recent improvements in the input physics and the effect of element diffusion within the stellar structures.…

Astrophysics · Physics 2009-10-31 V. Castellani , S. Degl'Innocenti , M. Marconi

Distances and absolute ages for the globular clusters NGC6397, NGC6752, and 47 Tuc are obtained using Main Sequence Fitting. Accurate reddenings and metal abundances (errors of 0.005 mag and 0.04 dex) are obtained by comparing B-V, b-y…

Previously [Y/Mg] has been proven to be an age indicator for solar twins. Here, we investigate if this relation also holds for helium-core-burning stars of solar metallicity. High resolution and high signal-to-noise ratio (S/N)…

Solar and Stellar Astrophysics · Physics 2017-08-16 D. Slumstrup , F. Grundahl , K. Brogaard , A. O. Thygesen , P. E. Nissen , J. Jessen-Hansen , V. Van Eylen , M. G. Pedersen

Globular Clusters (GCs) are natural laboratories where stellar and chemical evolution can be studied in detail. In addition, their chemical patterns and kinematics can tell us wich Galactic structure (Disk, Bulge, Halo or extragalactic) the…

Solar and Stellar Astrophysics · Physics 2018-01-10 A. Mura-Guzmán , S. Villanova , C. Muñoz , B. Tang

We report on a new, wide field ($20^{\prime} \times 20^{\prime}$), multicolor ($UBVI$), photometric campaign in the area of the nearby old open cluster NGC 2112. At the same time, we provide medium-resolution spectroscopy of 35 (and…

The study of old open clusters outside the solar circle can bring constraints on formation scenarios of the outer disk. In particular, accretion of dwarf galaxies has been proposed as a likely mechanism in the area. We use BVI photometry…

Astrophysics · Physics 2009-11-13 S. ortolani , E. Bica , B. Barbuy

NGC 6522 is a moderately metal-poor bulge globular cluster ([Fe/H]$\sim$$-$1.0), and it is a well-studied representative among a number of moderately metal-poor blue horizontal branch clusters located in the bulge. The NGC 6522 abundance…

We present a study of the star cluster population in the starburst irregular galaxy NGC 4449 based on B, V, I, and Ha images taken with the Advanced Camera for Surveys on the Hubble Space Telescope. We derive the cluster properties such as…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Francesca Annibali , Monica Tosi , Alessandra Aloisi , Roeland P. van der Marel

We examine the Mg-sigma relation for early-type galaxies in the EFAR sample and its dependence on cluster properties. A maximum likelihood fit gives global Mg-sigma relations of Mgb'=0.131log(sigma)-0.131 and Mg2=0.257log(sigma)-0.305, with…

We present new high resolution spectroscopic observations of the intermediate age (~2 Gyr) open cluster NGC 752. We investigate the Li vs. Teff distribution and we obtain a new accurate determination of the cluster metallicity. We compare…

Astrophysics · Physics 2009-11-10 P. Sestito , S. Randich , R. Pallavicini