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Related papers: Galactic Globular Cluster Relative Ages. II

200 papers

We present radial stellar population parameters for a subsample of 12 galaxies from the 36 isolated early-type galaxies of Reda et al. Using new long-slit spectra, central values and radial gradients for the stellar age, metallicity [Z/H]…

This work reports the discovery of three new globular clusters (GCs) towards the Galactic bulge - Camargo 1107, 1108, and 1109. The discovery was made using the WISE, 2MASS, VVV, and Gaia-DR2 photometry. The new findings are old (12.0-13.5…

Astrophysics of Galaxies · Physics 2019-01-25 Denilso Camargo , Dante Minniti

Visual and near-infrared colours are used to identify intermediate-age globular cluster in early-type galaxies. In NGC5846 and NGC4365 colour-colour diagrams (V-I vs. V-K) reveal a sub-population in the globular cluster systems with an age…

The differences in the relationships between the physical parameters and the chemical-element abundances in accreted globular star clusters and those formed inside the Galaxy have been investigated. The information on the supposed formation…

Astrophysics of Galaxies · Physics 2020-10-22 V. A. Marsakov , V. V. Koval' , M. L. Gozha

We have derived ages, metallicities and enhanced-element ratios [alpha/Fe] for a sample of 83 early-type galaxies essentially in groups, the field or isolated objects. The stellar population properties derived for each galaxy corresponds to…

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

We present a novel, observationally-based framework for the formation epochs and sites of globular clusters (GCs) in a cosmological context. Measuring directly the mean ages of the metal-poor and metal-rich GC subpopulations in our own…

Astrophysics of Galaxies · Physics 2015-08-06 Duncan A. Forbes , Nicola Pastorello , Aaron J. Romanowsky , Christopher Usher , Jean P. Brodie , Jay Strader

We report results that show that the straightforwardly star cluster metallicities obtained from Str\"omgren $vby$ photometry is age-dependent and need to be corrected for further use. This outcome arises from the comparison of [Fe/H] values…

Astrophysics of Galaxies · Physics 2020-10-14 Andrés E. Piatti

We discuss some of the key open questions regarding the formation and evolution of globular clusters (GCs) during galaxy formation and assembly within a cosmological framework. The current state-of-the-art for both observations and…

I propose and apply a method for deriving ages of the metal-poor globular clusters (GCs) in a distance-independent way, which is based on age indicator related to the main sequence in the two-color diagrams with U-B index. Age of the…

Astrophysics · Physics 2007-05-23 Valery V. Kravtsov

One of the largest sources of uncertainty in the computation of globular cluster isochrones and hence in the age determination of globular clusters is the lack of a rigorous description of convection. Therefore, we calibrated the…

Astrophysics · Physics 2009-10-31 Bernd Freytag , Maurizio Salaris

The Magellanic Clouds are the most massive and closest satellite galaxies of the Milky Way, with stars covering ages from a few Myr up to 13 Gyr. This makes them important for validating integrated light methods to study stellar populations…

Aims. We present a new technique to estimate the relative ages of multiple stellar populations hosted by five globular clusters: NGC 104 (47 Tuc), NGC 6121 (M4), NGC 6352, NGC 6362 and NGC 6723. Methods. We used the catalogs of the database…

Solar and Stellar Astrophysics · Physics 2021-02-17 F. Lucertini , D. Nardiello , G. Piotto

We investigate the old star clusters in the sample of cluster candidates from Froebrich, Scholz & Raftery 2007 -- the FSR list. Based on photometry from the 2-Micron All Sky Survey we generated decontaminated colour-magnitude and…

Astrophysics of Galaxies · Physics 2015-05-19 D. Froebrich , S. Schmeja , D. Samuel , P. W. Lucas

We have applied a new method to analyze the horizontal branch (HB) morphology in relation to the distribution of stars near the red giant branch (RGB) tip for the globular clusters M22, M5, M68, M107, M72, M92, M3 and 47 Tuc. This new…

Astrophysics · Physics 2015-06-24 R. Jimenez , P. Thejll , U. Jorgensen , J. MacDonald , B. Pagel

We present results derived from VLT-FORS2 spectra of 17 globular clusters associated with the nearby lenticular galaxy NGC3115. Comparing line-strength indices to new stellar population models by Thomas et al. we determine ages,…

Astrophysics · Physics 2007-05-23 Harald Kuntschner , Bodo L. Ziegler , R. M. Sharples , Guy Worthey , Klaus J. Fricke

We analyzed HST/WFPC2 colour-magnitude diagrams (CMDs) of 15 populous Large Magellanic Cloud (LMC) stellar clusters with ages between ~ 0.3 Gyr and ~ 3 Gyr. These (V, B-V) CMDs are photometrically homogeneous and typically reach V \~ 22.…

Astrophysics · Physics 2009-11-11 L. O. Kerber , B. X. Santiago , E. Brocato

This is the second paper of a series devoted to study the stellar content of early-type galaxies. The goal of the series is to set constraints on the evolutionary status of these objects. We use a new set of models which include an improved…

Astrophysics · Physics 2009-11-11 P. Sanchez-Blazquez , J. Gorgas , N. Cardiel , J. J. Gonzalez

We present spectroscopy of two clusters in the dwarf irregular galaxy NGC 6822. From these we deduce an age for Cluster VII of 11 Gyr and [Fe/H] = -1.95 +/- 0.15 dex. Cluster VII appears to be an analog of the metal-poor galactic globular…

Astrophysics · Physics 2009-10-30 Judith G. Cohen , John P. Blakeslee

We present new spectroscopic observations of a sample of globular clusters (GCs) in the Virgo Cluster elliptical NGC4365. The great majority of the objects analysed here, overlap on purpose with objects presented in two previous studies…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 A. L. Chies-Santos , S. S. Larsen , M. Kissler-Patig