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Related papers: The AMBRE Project: r-process elements in the Milky…

200 papers

Aims. The aim of this work is the study of abundances of the heavy elements Ba, La, Ce, Nd, and Eu in 56 bulge giants (red giant branch and red clump) with metallicities ranging from -1.3 dex to 0.5 dex. Methods. We obtained high-resolution…

Astrophysics of Galaxies · Physics 2016-01-20 M. Van der Swaelmen , B. Barbuy , V. Hill , M. Zoccali , D. Minniti , S. Ortolani , A. Gomez

This chapter presents an overview of the recent progress on spectroscopic observations of metal-poor stars with r-process element signatures found in the Milky Way's stellar halo and satellite dwarf galaxies. Major empirical lessons related…

Solar and Stellar Astrophysics · Physics 2023-02-24 Anna Frebel , Alexander P. Ji

We present an overview of the distributions of 11 elemental abundances in the Milky Way's inner regions, as traced by APOGEE stars released as part of SDSS Data Release 14/15 (DR14/DR15), including O, Mg, Si, Ca, Cr, Mn, Co, Ni, Na, Al, and…

The energy provided in the radioactive decay of thorium (Th) and uranium (U) isotopes, embedded in planetary mantles, sustains geodynamics important for surface habitability such as the generation of a planetary magnetic dynamo. In order to…

Solar and Stellar Astrophysics · Physics 2025-10-09 Evan M. Carrasco , Matthew Shetrone , Francis Nimmo , Enrico Ramirez-Ruiz , Joel Primack , Natalie M. Batalha

Neutron star mergers (NM) are a plausible source of heavy r-process elements such as Europium, but previous chemical evolution models have either failed to reproduce the observed Europium trends for Milky Way thick disc stars (with [Fe/H] ~…

Astrophysics of Galaxies · Physics 2019-05-29 Ralph Schönrich , David H. Weinberg

In this study we investigate the chemical enrichment of the rapid neutron-capture process in the Small Magellanic Cloud (SMC). We measure [Eu/Fe] abundance ratios in 209 giant stars that are confirmed members of the SMC, providing the first…

Astrophysics of Galaxies · Physics 2025-11-13 Samuele Anoardo , Alessio Mucciarelli , Marco Palla , Lorenzo Santarelli , Carmela Lardo , Donatella Romano

Observational data have revealed a clear dichotomy in the [{\alpha}/Fe] vs. [Fe/H] diagram of the Milky Way thick and thin disc stars. Many recent studies have shown evidences of a co-evolution phase between the high- and low-{\alpha} disc…

Astrophysics of Galaxies · Physics 2026-05-12 V. Grisoni , E. Spitoni , F. Matteucci

Recent spectroscopic studies have revealed the presence of numerous carbon-enhanced, metal-poor stars with [Fe/H] < -2.0 that exhibit strong enhancements of s-process elements. These stars are believed to be the result of a binary…

Astrophysics · Physics 2009-11-13 S. Wanajo , K. Nomoto , N. Iwamoto , Y. Ishimaru , T. C. Beers

We have studied 23 long-lived G dwarfs that belong to the thin disk and thick disk stellar populations. Abundances have been derived for 24 elements: O, Na, Mg, Al, Si, Ca, Ti, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd,…

Astrophysics · Physics 2008-11-26 Mary-Margaret Brewer , Bruce W. Carney

Recent progress of nucleosynthesis work as well as the discovery of a kilonova associated with the gravitational-wave source GW170817 indicates that neutron star mergers (NSM) can be a site of the r-process. Several studies of galactic…

Astrophysics of Galaxies · Physics 2021-07-14 Shinya Wanajo , Yutaka Hirai , Nikos Prantzos

To understand the formation of the Milky Way's prominent bar it is important to know whether stars in the bar differ in the chemical element composition of their birth material as compared to disk stars. This requires stellar abundance…

The element abundances of Milky Way disc stars encode entangled imprints of multiple enrichment processes, making it difficult to uncover the underlying chemical evolution. Here we re-project 16 stellar abundances for 199,290 red giant…

We present the results of a detailed abundance analysis of one of the confirmed building blocks of the Milky Way stellar halo, a kinematically-coherent metal-poor stellar stream. We have obtained high resolution and high S/N spectra of 12…

Astrophysics of Galaxies · Physics 2015-05-14 Ian U. Roederer , Christopher Sneden , Ian B. Thompson , George W. Preston , Stephen A. Shectman

We present the distributions of elemental abundance ratios using chemodynamical simulations which include four different neutron capture processes: magneto-rotational supernovae, neutron star mergers, neutrino driven winds, and electron…

Astrophysics of Galaxies · Physics 2018-12-19 Christopher Haynes , Chiaki Kobayashi

We study turbulent gas diffusion affects on $r$-process abundances in Milky Way stars, by a combination of an analytical approach and a Monte Carlo simulation. Higher $r$-process event rates and faster diffusion, lead to more efficient…

High Energy Astrophysical Phenomena · Physics 2020-06-24 Paz Beniamini , Kenta Hotokezaka

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…

We present a detailed study of the chemical diversity of the metal-poor Milky Way (MW) using data from the GALAH DR3 survey. Considering 17 chemical abundances relative to iron ([X/Fe]) for 9,923 stars, we employ Principal Component…

Astrophysics of Galaxies · Physics 2024-07-29 Nicole Buckley , Payel Das , Paula Jofré , Robert M. Yates , Keith Hawkins

We use cosmological, magnetohydrodynamical simulations of Milky Way-mass galaxies from the Auriga project to study their enrichment with rapid neutron capture (r-process) elements. We implement a variety of enrichment models from both…

We combine stellar orbits with the abundances of the heavy, $r$-process element europium and the light, $\alpha$-element, silicon to separate in-situ and accreted populations in the Milky Way across all metallicities. At high orbital…

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