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Related papers: Age and Metallicity Effects in Omega Centauri

200 papers

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

We have performed multivariate statistical analyses of photometric and chemical abundance parameters of three large samples of stars in the globular cluster $\omega$ Centauri. The statistical analysis of a sample of 735 stars based on seven…

Astrophysics of Galaxies · Physics 2015-05-28 Didier Fraix-Burnet , E. Davoust

We report metallicities for three $\sim$Gyr-old stars in the Milky Way nuclear star cluster (NSC) using high-resolution near-infrared spectroscopy. We derive effective temperatures from a calibration with Sc line strength, which yields…

We perform a combined analysis of stellar kinematics and line-of-sight accelerations of millisecond pulsars to investigate the mass contents of Omega Centauri. We consider multiple mass components: the visible photometric distribution, a…

Astrophysics of Galaxies · Physics 2025-01-15 Andrés Bañares-Hernández , Francesca Calore , Jorge Martin Camalich , Justin I. Read

In response to the proposed high helium content stars as an explanation for the double main sequence observed in Omega Centauri, we investigated the consequences of such stars elsewhere on the color-magnitude diagram. We concentrated on the…

Astrophysics · Physics 2009-06-23 G. Newsham , D. M. Terndrup

In some scenarios for the formation of the Milky Way bulge the stellar population at the edges of the boxy bulge may be younger than those on the minor axis, or close to the Galactic center. So far the only bulge region where deep…

Astrophysics of Galaxies · Physics 2015-06-17 E. Valenti , M. Zoccali , A. Renzini , T. M. Brown , O. Gonzalez , D. Minniti , Victor P. Debattista , L. Mayer

We studied the relationship between the average stellar abundance of several elements and the orbital evolution of stars in the neighbourhood of the Sun, using both observational data for 325 late-type dwarfs in a volume-complete sample and…

We select from Paper I a sample of 306 massive star clusters observed with the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) in the vicinity fields of M31 and M33 and determine their metallicities, ages and masses.…

The gravitational interactions between the Milky Way and in-falling satellites offer a wealth of information about the formation and evolution of our Galaxy. In this paper, we explore the high-dimensionality of the GALAH DR3 plus Gaia eDR3…

Astrophysics of Galaxies · Physics 2023-07-12 Kris Youakim , Karin Lind , Iryna Kushniruk

An analysis of ages, metallicities, and [alpha/Fe] ratios of globular cluster systems in early-type galaxies is presented, based on Lick index measurements summarized in Puzia et al. (2004, Paper I of this series). In the light of…

We focus on an analysis of galaxies of high stellar mass and low metallicity. We cross-correlated the Millenium Galaxy Catalogue (MGC) and the Sloan Digital Sky Survey (SDSS) galaxy catalogue to provide a sample of MGC objects with high…

Cosmology and Nongalactic Astrophysics · Physics 2010-02-20 M. S. Alonso , L. Michel-Dansac , D. G. Lambas

We present new measurements of the metallicity of 131 RR Lyrae stars in the globular cluster Omega Centauri, using the hk index of the Caby photometric system. The hk method has distinct advantages over Delta-S and other techniques in…

Astrophysics · Physics 2009-10-31 Soo-Chang Rey , Young-Wook Lee , Jong-Myung Joo , Alistair Walker , Scott Baird

We here present the results of an analysis of the optical spectroscopy of 42 globular cluster (GC) candidates in the nearby spiral galaxy M81 (3.61~Mpc). The spectra were obtained using the long-slit and MOS modes of the OSIRIS instrument…

We present a statistical analysis of the ages and metallicities of triple stellar systems that are known to host exoplanets. With controversial cases disregarded, so far 27 of those systems have been identified. Our analysis, based on an…

Solar and Stellar Astrophysics · Physics 2024-08-26 Manfred Cuntz , Shaan D. Patel

We review the possibility that metallicity could provide a diagnostic for the age of a galaxy, hence that the most metal-poor star forming galaxies in the local universe may be genuinely young. Indeed, observational evidence for downsizing…

Astrophysics · Physics 2015-05-13 Daniel Kunth , Goran Ostlin

We interpret the stellar population of $\omega$ Centauri by means of a population synthesis analysis, following the most recent observational guidelines for input metallicities, helium and [(C+N+O)/Fe] contents. We deal at the same time…

Solar and Stellar Astrophysics · Physics 2016-02-17 Marco Tailo , Marcella Di Criscienzo , Francesca D'Antona , Vittoria Caloi , Paolo Ventura

HST trigonometric distances, photometric metallicities, isochronic ages from the second revised version of the Geneva--Copenhagen survey, and uniform spectroscopic Fe and Mg abundances from our master catalog are used to construct and…

Astrophysics of Galaxies · Physics 2015-05-28 V. A. Marsakov , V. V. Koval' , T. V. Borkova , M. V. Shapovalov

From X-ray observations of galaxy clusters one derives the mass of the intracluster medium along with its chemical composition. Optical/infrared observations are used to estimate the mass of the stellar components of galaxies, along with…

Astrophysics · Physics 2007-05-23 Alvio Renzini

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

Using current observational data and simple dynamical modeling, we demonstrate that Omega Cen is not special among the Galactic globular clusters in its ability to produce and retain the heavy elements dispersed in the AGB phase of stellar…

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