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Related papers: Enrichment of r-process elements in dwarf spheroid…

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Understanding the abundance pattern of metal-poor stars and the production of heavy elements through various nucleosynthesis processes offers crucial insights into the chemical evolution of the Milky Way, revealing primary sites and major…

Half of all the elements in the universe heavier than iron were created by rapid neutron capture. The theory for this astrophysical `$r$-process' was worked out six decades ago and requires an enormous neutron flux to make the bulk of these…

The astrophysical origin of elements synthesized through the rapid neutron capture process ($r-$process) is a long standing mystery. The hot and dense environments of core-collapse supernovae have been suggested as potential $r-$process…

High Energy Astrophysical Phenomena · Physics 2025-07-03 Tejas Prasanna , Matthew S. B. Coleman , Todd A. Thompson , Brian D. Metzger , Anirudh Patel , Bradley S. Meyer

Recent calculations place questions on the ability of supernovae to produce r-process nuclei in the correct amounts. We present results from 3D Newtonian SPH calculations of mergers of equal mass neutron star binaries. We find the amounts…

Astrophysics · Physics 2016-08-30 S. Rosswog , F. -K. Thielemann , M. B. Davies , W. Benz , T. Piran

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

We examine the r-process in the neutrino-driven proto-neutron-star (PNS) wind of core-collapse supernovae in light of the recent findings of massive neutron stars in binaries as well as of an indication of neutron-richness in the PNS ejecta…

Solar and Stellar Astrophysics · Physics 2015-06-15 Shinya Wanajo

We present high-resolution Magellan/MIKE spectra of 22 bright ($9<V<13.5$) metal-poor stars ($-3.18<\mbox{[Fe/H]}<-1.37$) in three different stellar streams, the Helmi debris stream, the Helmi trail stream, and the $\omega$ Centauri…

Solar and Stellar Astrophysics · Physics 2021-05-12 Maude Gull , Anna Frebel , Karina Hinojosa , Ian U. Roederer , Alexander P. Ji , Kaley Brauer

(Abridged) Many dwarf galaxies exhibit sub-Solar metallicities, with some star-to-star variation, despite often containing multiple generations of stars. The total metal content in these systems is much less than expected from the heavy…

Astrophysics · Physics 2009-11-07 P. Chris Fragile , Stephen D. Murray , Peter Anninos , Douglas N. C. Lin

Heavy elements like gold, platinum or uranium are produced in the r-process, which needs neutron-rich and explosive environments. Neutron star mergers are a promising candidate for an r-process site. They exhibit three different channels…

Solar and Stellar Astrophysics · Physics 2015-09-28 Dirk Martin , Albino Perego , Almudena Arcones , Oleg Korobkin , Friedrich-Karl Thielemann

The Keck I telescope has been used to obtain HIRES spectra for red giants belonging to the Draco, Sextans and Ursa Minor dwarf spheroidal (dSph) galaxies. An analysis of these spectra is presented, along with abundance ratios for more than…

Astrophysics · Physics 2011-08-23 Matthew Shetrone , Patrick Cote , W. L. W. Sargent

The stellar record of elemental abundances in satellite galaxies is important to identify the origin of r-process because such a small stellar system could have hosted a single r-process event, which would distinguish member stars that are…

Solar and Stellar Astrophysics · Physics 2017-11-29 Takuji Tsujimoto , Tadafumi Matsuno , Wako Aoki , Miho N. Ishigaki , Toshikazu Shigeyama

About half of the elements beyond iron are synthesized in stars by rapid-neutron capture process (r-process). The stellar environment provides very high neutron flux in a short time ($\sim$ seconds) which is conducive for the creation of…

Nuclear Theory · Physics 2023-06-05 Vinay Singh , Joydev Lahiri , Malay Kanti Dey , D. N. Basu

We present detailed chemical element abundance ratios of 17 elements in three metal poor stars in the Ursa Minor dwarf spheroidal galaxy, which we combine with extant data from the literature to assess the predictions of a novel suite of…

Astrophysics of Galaxies · Physics 2015-06-23 Ugur Ural , Gabriele Cescutti , Andreas Koch , Jan Kleyna , Sofia Feltzing , Mark I. Wilkinson

The merger of binary neutron stars, or of a neutron star and a stellar-mass black hole, can result in the formation of a massive rotating torus around a spinning black hole. In addition to providing collimating media for gamma-ray burst…

High Energy Astrophysical Phenomena · Physics 2017-12-13 Daniel M. Siegel , Brian D. Metzger

We study galactic enrichment with rapid neutron capture (r-process) elements in cosmological, magnetohydrodynamical simulations of a Milky Way-mass galaxy. We include a variety of enrichment models, based on either neutron star mergers or a…

Astrophysics of Galaxies · Physics 2022-03-30 Freeke van de Voort , Rüdiger Pakmor , Rebekka Bieri , Robert J. J. Grand

A renewed interest about the origin of \emph{r}-process elements has been stimulated by the multi-messenger observation of the gravitational event GW170817, with the detection of both gravitational waves and electromagnetic waves…

We present a detailed analysis of the composition and nucleosynthetic origins of the heavy elements in the metal-poor ([Fe/H]=-1.62+/-0.09) star HD94028. Previous studies revealed that this star is mildly enhanced in elements produced by…

Solar and Stellar Astrophysics · Physics 2016-04-20 Ian U. Roederer , Amanda I. Karakas , Marco Pignatari , Falk Herwig

We follow the chemical evolution of the Galaxy for elements from Ba to Eu, using an evolutionary model suitable to reproduce a large set of Galactic (local and non local) and extragalactic constraints. Input stellar yields for neutron-rich…

Astrophysics · Physics 2009-10-31 C. Travaglio , D. Galli , R. Gallino , M. Busso , F. Ferrini , O. Straniero

We analyze the production of the element Cr in galactic chemical evolution (GCE) models using the NuGrid nucleosynthesis yields set. We show that the unusually large [Cr/Fe] abundance at [Fe/H] $\approx 0$ reported by previous studies using…

Solar and Stellar Astrophysics · Physics 2020-04-08 Benoit Côté , Samuel Jones , Falk Herwig , Marco Pignatari

In this work, we compute rates of merging neutron stars (MNS) in galaxies of different morphological type, as well as the cosmic MNS rate in a unitary volume of the Universe adopting different cosmological scenarios. Our aim is to provide…

Astrophysics of Galaxies · Physics 2021-02-01 Marta Molero , Paolo Simonetti , Francesca Matteucci , Massimo della Valle
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