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Related papers: The temporal evolution of neutron-capture elements…

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The physical processes driving chemical evolution in the Milky Way can be probed using the distribution of abundances in low-mass FGK type stars in space phase at different times. During their final stages of evolution stars experience…

Solar and Stellar Astrophysics · Physics 2020-01-15 Paula Jofre , Holly Jackson , Marcelo Tucci Maia

The aim of this work is to determine abundances of neutron-capture elements for thin- and thick-disc F, G, and K stars in several sky fields near the north ecliptic pole and to compare the results with the Galactic chemical evolution…

Context: The chemical composition of stars is intimately linked to the Galaxy formation and evolution. Aims: We aim to trace the chemical evolution of the Galactic disk through the inspection of the [X/Fe]-age relations of 24 species from C…

Solar and Stellar Astrophysics · Physics 2016-10-05 L. Spina , J. Meléndez , A. I. Karakas , I. Ramírez , T. R. Monroe , M. Asplund , D. Yong

HARPS spectra with S/N > 600 for 21 solar twin stars are used to determine very precise (sigma ~ 0.01 dex) differential abundances of C, O, Na, Mg, Al, Si, S, Ca, Ti, Cr, Fe, Ni, Zn, and Y in order to see how well [X/Fe] is correlated with…

Solar and Stellar Astrophysics · Physics 2015-07-01 Poul E. Nissen

Context: Studies based on high-precision abundance determinations revealed that chemical patterns of solar twins are characterised by the correlation between the differential abundances relative to the Sun and the condensation temperatures…

Solar and Stellar Astrophysics · Physics 2016-01-20 Lorenzo Spina , Jorge Meléndez , Ivan Ramírez

A previous study of correlations between element abundance ratios, [X/Fe], and ages of solar twin stars is extended to include Sc, Mn, Cu, and Ba. HARPS spectra with S/N > 600 are used to derive very precise (+/- 0.01 dex) differential…

Solar and Stellar Astrophysics · Physics 2016-09-21 P. E. Nissen

Chemical clocks based on [s-process elements/alpha-elements] ratios are widely used to estimate ages of Galactic stellar populations. However, the [s/alpha] vs. age relations are not universal, varying with metallicity, location in the…

Abundances of light elements in dwarf stars of different ages are important constraints for stellar yields, Galactic chemical evolution and exoplanet chemical composition studies. We have measured C and N abundances and $^{12}$C/$^{13}$C…

Solar and Stellar Astrophysics · Physics 2020-10-07 Rafael Botelho , Andre Milone , Jorge Melendez , Alan Alves-Brito , Lorenzo Spina , Jacob Beans

The primary objective of this study is to accurately determine the abundances of Cu, Sr, Y, Zr, Ba, La, and Ce in selected solar-type stars. This will allow us to establish observational abundance-metallicity and abundance-age relations and…

Solar and Stellar Astrophysics · Physics 2024-07-23 Valentina Sheminova , Martina Baratella , Valentina D'Orazi

The enrichment history of heavy neutron-capture elements in the Milky Way disc provides fundamental information about the chemical evolution of our Galaxy and about the stellar sources that made those elements. In this work we give new…

Astrophysics of Galaxies · Physics 2019-02-13 T. Mishenina , M. Pignatari , T. Gorbaneva , S. Bisterzo , C. Travaglio , F. K. Thielemann , C. Soubiran

An ensemble of chemical abundances probing different nucleosynthetic channels can be leveraged to build a comprehensive understanding of the chemical and structural evolution of the Galaxy. Using GALAH DR3 data, we seek to trace the…

Astrophysics of Galaxies · Physics 2022-05-25 Danny Horta , Melissa K. Ness , Jan Rybizki , Ricardo P. Schiavon , Sven Buder

In a recent study, based on homogeneous barium abundance measurements in open clusters, a trend of increasing [Ba/Fe] ratios for decreasing cluster age was reported. We present here further abundance determinations, relative to four other…

Solar and Stellar Astrophysics · Physics 2015-05-28 E. Maiorca , S. Randich , M. Busso , L. Magrini , S. Palmerini

Knowledge of abundance ratios as functions of metallicity can lead to insights on the origin and evolution of our Galaxy and its stellar populations. We aim to trace the chemical evolution of the neutron-capture elements Sr, Zr, La, Ce, Nd,…

Solar and Stellar Astrophysics · Physics 2017-04-26 Chiara Battistini , Thomas Bensby

[ABRIDGED] The purpose of this work is to evaluate how several elements produced by different nucleosynthesis processes behave with stellar age and provide empirical relations to derive stellar ages from chemical abundances. We derive…

Photospheric abundances are presented for 27 elements from carbon to europium in 181 F-G dwarfs from a differential LTE analysis of high-resolution and high signal-to-noise spectra. Stellar $T_{\rm eff}$ were adopted from an infrared flux…

Astrophysics · Physics 2009-11-07 Bacham E. Reddy , Jocelyn Tomkin , David L. Lambert , Carlos Allende Prieto

The heavy elements formed by neutron capture processes have an interesting history from which we can extract useful clues to and constraints upon both the characteristics of the processes themselves and the star formation and…

Astrophysics · Physics 2009-11-07 J. W. Truran , J. J. Cowan , C. A. Pilachowski , C. Sneden

We present the chemical abundances of Fe, alpha- and neutron-capture elements in 12 metal-poor Small Magellanic Cloud (SMC) giant stars, observed with the high-resolution spectrographs UVES/VLT and MIKE/Magellan. These stars have [Fe/H]…

The chemical evolution of neutron capture elements in the Milky Way disc is still a matter of debate. We aim to understand the chemical evolution of r-process elements in Milky Way disc. We focus on three pure r-process elements Eu, Gd, and…

Astrophysics of Galaxies · Physics 2018-11-28 G. Guiglion , P. de Laverny , A. Recio-Blanco , N. Prantzos

Several works have found an increase of the abundances of the s-process neutron-capture elements in the youngest Galactic stellar populations, giving important constraints to stellar and Galactic evolution. We aim to trace the abundance…

We study the chemical evolution of Zr, La, Ce and Eu in the Milky Way discs and bulge by means of chemical evolution models compared with recent spectroscopic data. We consider detailed chemical evolution models for the Galactic thick disc,…

Astrophysics of Galaxies · Physics 2020-01-15 V. Grisoni , G. Cescutti , F. Matteucci , R. Forsberg , H. Jönsson , N. Ryde
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