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Related papers: A possible age-metallicity relation in the Galacti…

200 papers

The age-metallicity relation (AMR) is a fundamental observational constraint for understanding the chemical evolution of the Galaxy. As reliable cosmochronometers, white dwarfs in binary systems with main sequence companions (WD+MS…

Solar and Stellar Astrophysics · Physics 2026-05-27 Alberto Rebassa-Mansergas , Iset Tejero-Gómez , Roberto Raddi

We have undertaken the study of the elemental abundances and kinematic properties of a metal-poor sample of candidate thick-disk stars selected from the RAVE spectroscopic survey of bright stars to differentiate among the present scenarios…

The variation of metal production over time and its dilution in the interstellar medium depend on the star formation and gas accretion rates. Measuring age-chemistry relations across the Milky Way disk provides key constraints on the gas…

Astrophysics of Galaxies · Physics 2025-05-28 Valeria Cerqui , Misha Haywood , Owain Snaith , Paola Di Matteo , Laia Casamiquela

The abundances of iron and oxygen are homogeneously determined in a sample of 523 nearby (d<150 pc) FGK disk and halo stars with metallicities in the range -1.5<[Fe/H]<0.5. The oxygen abundances were inferred from a restricted non-LTE…

Astrophysics · Physics 2009-11-13 I. Ramirez , C. Allende Prieto , D. L. Lambert

We determined the chemical and kinematic properties of the Galactic thin and thick disk using a sample of 307,246 A/F/G/K-type giant stars from the LAMOST spectroscopic survey and Gaia DR2 survey. Our study found that the thick disk…

Astrophysics of Galaxies · Physics 2019-07-31 Yepeng Yan , Cuihua Du , Shuai Liu , Hefan Li , Jianrong Shi , Yuqin Chen , Jun Ma , Zhenyu Wu

We performed an uniform spectroscopic analysis of 1111 FGK dwarfs observed as part of the HARPS GTO planet search program. We applied a purely chemical approach, based on [alpha/Fe] ratio, to distinguish the various stellar components in…

Earth and Planetary Astrophysics · Physics 2013-07-09 V. Zh. Adibekyan , N. C. Santos , S. G. Sousa , G. Israelian , P. Figueira

The age-metallicity relation is fundamental to study the formation and evolution of the disk. Observations have shown that this relation has a large scatter which can not be explained by observational errors only. That scatter is hence…

Astrophysics of Galaxies · Physics 2021-10-20 Paula Jofre

We use 297 042 main sequence turn-off stars selected from the LSS-GAC to determine the radial and vertical gradients of stellar metallicity of the Galactic disk in the anti-center direction. We determine ages of those turn-off stars by…

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…

It has been suggested that the high metallicity generally observed in active galactic nuclei (AGNs) and quasars originates from ongoing star formation in the self-gravitating part of accretion disks around the supermassive black holes. We…

Astrophysics of Galaxies · Physics 2015-05-28 J. -M. Wang , J. -Q. Ge , C. Hu , J. A. Baldwin , Y. -R. Li , G. J. Ferland , F. Xiang , C. -S. Yan , S. Zhang

We analyze the radial and vertical metallicity and [alpha/Fe] gradients of the disk stars of a disk galaxy simulated in a fully cosmological setting with the chemodynamical galaxy evolution code, GCD+. We study how the radial abundance…

Astrophysics of Galaxies · Physics 2015-06-16 Awat Rahimi , Kenneth Carrell , Daisuke Kawata

(Abridged) The present-day spatial and kinematic distribution of stars in the Milky Way provides key constraints on its internal dynamics and evolutionary history. We select stars that are more metal-rich than the interstellar medium (ISM)…

Stellar ages are an important parameter to study the chemical evolution of the Galaxy. In recent years, several studies have established the existence of a relationship between chemical clocks and stellar ages. The [Y/Mg] clock is a…

Astrophysics of Galaxies · Physics 2024-10-02 J. Shejeelammal , Jorge Meléndez , Anne Rathsam , Giulia Martos

We study the structure, age and metallicity gradients, and dynamical evolution using a cosmological zoom-in simulation of a Milky Way-mass galaxy from the Feedback in Realistic Environments project. In the simulation, stars older than 6 Gyr…

We present results from the largest CaII triplet line metallicity study of Small Magellanic Cloud (SMC) field red giant stars to date, involving 3037 objects spread across approximately 37.5 sq. deg., centred on this galaxy. We find a…

Astrophysics of Galaxies · Physics 2015-06-19 P. D. Dobbie , A. A. Cole , A. Subramaniam , S. Keller

The problem of the chemical composition gradient in the galactic disk is studied based on a sample of metallicity estimates of open star clusters, using Gaia DR2-improved distance estimates. A clearly non-monotonic variation was observed in…

Solar and Stellar Astrophysics · Physics 2020-05-06 A. V. Loktin , M. E. Popova

We use recently derived ages for 61 Milky Way (MW) globular clusters (GCs) to show that their age-metallicity relation (AMR) can be divided into two distinct, parallel sequences at [Fe/H] $\ga -1.8$. Approximately one-third of the clusters…

Astrophysics of Galaxies · Physics 2015-06-17 Ryan Leaman , Don A. VandenBerg , J. Trevor Mendel

The vertical metallicity gradient of the Galactic disk offers valuable insights into the disk's formation and chemical evolution over time. We utilized the LAMOST-LRS young stellar sample to investigate this gradient and found that it…

Astrophysics of Galaxies · Physics 2025-04-03 Gaohuan Long , Haibo Yuan , Shuai Xu , Chun Wang , Ruoyi Zhang , Bowen Huang

Stellar ages are a crucial component to studying the evolution of the Milky Way. Using Gaia DR2 distance estimates, it is now possible to estimate stellar ages for a larger volume of evolved stars through isochrone matching. This work…

We address the question of the occurrence of star formation bursts in the solar neighbourhood by using the metallicity distribution of the G dwarfs. We present a method to recover the star formation history using simultaneously the…

Astrophysics · Physics 2015-06-24 Helio J. Rocha-Pinto , Walter J. Maciel