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Related papers: Measuring Ages and Elemental Abundances from Unres…

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We study the ages of $\alpha$-rich and $\alpha$-poor stars in the halo using a sample of F and G dwarfs from the Sloan Digital Sky Survey (SDSS). To separate stars based on [$\alpha$/Fe], we have developed a new semi-empirical…

Astrophysics of Galaxies · Physics 2015-06-22 Keith Hawkins , Paula Jofre , Gerry Gilmore , Thomas Masseron

As part of an ongoing program to measure detailed chemical abundances in nearby galaxies, we use a sample of young to intermediate age clusters in the Large Magellanic Cloud with ages of 10 Myr to 2 Gyr to evaluate the effect of isochrone…

Solar and Stellar Astrophysics · Physics 2015-06-04 J. E. Colucci , R. A. Bernstein

We present the elemental abundances and ages of 19 massive quiescent galaxies at $z\sim1.4$ and $z\sim2.1$ from the Keck Heavy Metal Survey. The ultra-deep LRIS and MOSFIRE spectra were modeled using a full-spectrum stellar population…

The last decade has seen a revolution in our knowledge of the Galaxy thanks to the Gaia and asteroseismic space missions and the ground-based spectroscopic surveys. To complete this picture, it is necessary to map the ages of its stellar…

The large amount of spectra obtained during the epoch of extensive spectroscopic surveys of Galactic stars needs the development of automatic procedures to derive their atmospheric parameters and individual element abundances. Starting from…

Estimating age distributions, or star formation histories, of stellar populations in the Milky Way is important in order to study the evolution of trends in elemental abundances and kinematics. We build on previous work to develop an…

Instrumentation and Methods for Astrophysics · Physics 2021-01-20 Christian L. Sahlholdt , Lennart Lindegren

The age, evolution, and chemical properties of the Galactic disk can be effectively ascertained using open clusters. Within the large program Stellar Populations Astrophysics at the Telescopio Nazionale Galileo, we specifically focused on…

The abundance ratios of some chemical species have been found to correlate with stellar age, leading to the possibility of using stellar atmospheric abundances as stellar age indicators. These chemical clocks have been calibrated with…

Solar and Stellar Astrophysics · Physics 2021-10-27 Francisca Espinoza-Rojas , Julio Chanamé , Paula Jofré , Laia Casamiquela

We have analyzed high-resolution and high signal-to-noise ratio optical spectra of nearby FGK stars with and without detected giant planets in order to homogeneously measure their photospheric parameters, mass, age, and the abundances of…

Solar and Stellar Astrophysics · Physics 2015-07-29 R. da Silva , A. C. Milone , H. J. Rocha-Pinto

We derive stellar metallicities, light-weighted ages and stellar masses for a magnitude-limited sample of 175,128 galaxies drawn from the Sloan Digital Sky Survey Data Release Two (SDSS DR2). We compute median-likelihood estimates of these…

We explore the structure of the element abundance--age--orbit distribution of the stars in the Milky Way's low-$\alpha$ disk, by (re-)deriving precise [Fe/H], [X/Fe] and ages, along with orbits, for red clump stars from the APOGEE survey.…

Solar and Stellar Astrophysics · Physics 2019-10-09 Melissa K. Ness , Kathryn V. Johnston , Kirsten Blancato , Hans-Walter Rix , Angus Beane , Jonathan C. Bird , Keith Hawkins

We present a Bayesian implementation of isochrone fitting in deriving stellar ages and masses, incorporating absolute K magnitude ($\rm M_K$) derived from 2MASS photometry and Gaia DR1 parallax and differentiation between initial bulk…

Solar and Stellar Astrophysics · Physics 2018-03-30 Jane Lin , Aaron Dotter , Yuan-Sen Ting , Martin Asplund

We have previously reported on chemical abundance trends with evolutionary state in the globular cluster NGC 6397 discovered in analyses of spectra taken with FLAMES at the VLT. Here, we reinvestigate the FLAMES-UVES sample of 18 stars,…

Solar and Stellar Astrophysics · Physics 2012-09-24 T. Nordlander , A. J. Korn , O. Richard , K. Lind

We present chemical abundance measurements for 7,302 red giant branch stars within the half-light radius (~5') of $\omega$ Centauri ($\omega$ Cen), derived from MUSE spectra using the neural network model DD-Payne. DD-Payne effectively…

CONTEXT:The detailed chemical abundances of extremely metal-poor (EMP) stars are key guides to understanding the early chemical evolution of the Galaxy. Most existing data are, however, for giant stars which may have experienced internal…

Differences in chemical composition among main sequence stars within a given cluster are probably due to differences in their masses and other effects such as radiative diffusion, magnetic field, rotation, mixing mechanisms, mass loss,…

Solar and Stellar Astrophysics · Physics 2014-01-21 T. Kilicoglu , R. Monier , L. Fossati

The age and chemical composition of the stars in present-day galaxies carry important clues about their star formation processes. The latest generation of population synthesis models have allowed to derive age and stellar metallicity…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Anna Gallazzi

Exploring the Galactic chemical evolution and enrichment scenarios with open clusters allows us to understand the history of the Milky Way disk. High-resolution spectra of OCs are a crucial tool, as they provide precise chemical…

Local galaxies follow scaling relations between mass and stellar population properties such as age and metallicity, which encode key information on their evolutionary histories. We revise these relations using the largest spectroscopic…

Astrophysics of Galaxies · Physics 2025-11-05 D. Mattolini , S. Zibetti , A. R. Gallazzi , L. Scholz-Diaz , J. Pratesi

High resolution integrated light (IL) spectroscopy provides detailed abundances of distant globular clusters whose stars cannot be resolved. Abundance comparisons with other systems (e.g. for chemical tagging) require understanding the…

Astrophysics of Galaxies · Physics 2015-06-22 Charli M. Sakari , Kim Venn , Matthew Shetrone , Aaron Dotter , Dougal Mackey