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Related papers: The Age of Globular Clusters

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Despite the rapid observational progress in the study of young massive star clusters, the formation of globular clusters still remains poorly understood. Yet, it is emerging that globular cluster formation is intimately linked to the…

Astrophysics · Physics 2009-11-07 Oleg Y. Gnedin

We have derived ages and metallicities from co-added spectra of 131 globular clusters associated with the giant elliptical galaxy NGC 4472. Based upon a calibration with Galactic globular clusters, we find that our sample of globular…

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

Despite the tremendous advance of observational cosmology, the value of the Hubble constant ($H_0$) is still controversial (the so called ``Hubble tension'') because of the inconsistency between local/late-time measurements and those…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-19 Andrea Cimatti , Michele Moresco

(ABRIDGED) We assess the systematic uncertainties in (young) cluster age, mass, and - to a lesser extent - extinction and metallicity determinations, based on broad-band imaging observations with the Hubble Space Telescope. Our aim here is…

This paper supplements Jiang et al. (2003), who studied 172 M31 globular clusters (GCs) and globular cluster candidates from Battistini et al. (1987) on the basis of integrated photometric measurements in the…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Jun Ma , Zhou Fan , Richard de Grijs , Zhenyu Wu , Xu Zhou , Jianghua Wu

We present the results of a meta-analysis of Keck spectra of extragalactic globular clusters (GCs) in a sample of eight galaxies, ranging from dwarfs to massive ellipticals. We infer ages for the metal-poor and metal-rich GCs in these…

Astrophysics · Physics 2019-08-15 Jay Strader , Jean P. Brodie , A. J. Cenarro , Michael A. Beasley , Duncan A. Forbes

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

We present spectroscopic ages, metallicities, and [alpha/Fe] ratios for 70 globular clusters in M31 that were derived from Lick line-index measurements. In addition to a population of old (>10 Gyr) globular clusters with a wide range of…

Astrophysics · Physics 2009-11-10 Thomas H. Puzia , Kathy M. Perrett , Terry J. Bridges

Old Globular Clusters (GCs) in the Milky Way have ages of about 13 Gyr, placing their formation time in the reionization epoch. We propose a novel scenario for the formation of these systems based on the merger of two or more atomic cooling…

Astrophysics of Galaxies · Physics 2022-01-24 Michele Trenti , Paolo Padoan , Raul Jimenez

Globular clusters are among the first objects used to establish the distance scale of the Universe. In the 1970-ies it has been recognized that the differential magnitude distribution of old globular clusters is very similar in different…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-20 M. Rejkuba

A meta-analysis of seismic ages determined for individual stars in the well-studied open and globular clusters NGC 6819, NGC 6791, M67, M4, M19, M80, and M9 reveals both high variance across measurements and significant discrepancy with…

Solar and Stellar Astrophysics · Physics 2025-02-14 Jamie Tayar , Meridith Joyce

In previous papers of the series we used a combination of optical and near-infrared colours to derive constraints on the relative age structure in globular cluster systems. Here, we present the details, strength and limitations of our…

Astrophysics · Physics 2009-11-10 Maren Hempel , Markus Kissler-Patig

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

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

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

In the Large Magellanic Cloud (LMC), there have been very few clusters observed with ages between 4 and 11 Gyr. This phenomenon is sometimes referred to as the `LMC age gap'. We constructed a model of the cluster age distribution aimed at…

Astrophysics of Galaxies · Physics 2026-05-12 Jonathan H. Klos , Andrés E. Piatti

The ages of globular clusters in our own Milky Way are known with precision of about \pm 1 Gyr, hence their formation at redshifts z>~3 and their role in hierarchical cosmology and the reionization of the intergalactic medium remain…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Harley Katz , Massimo Ricotti

We present a new independent determination for the age of one of the oldest open clusters, NGC 188: $6.41 \pm 0.33$ Gyr. We utilize a novel approach where we jointly fit the radial velocities (RVs) and spectral energy distributions (SED) of…

Solar and Stellar Astrophysics · Physics 2025-08-14 K. Yakut , B. Kalomeni , S. Rappaport
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