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Related papers: Changes in r-process abundances at late times

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Recent observations of r-process-enriched metal-poor star abundances reveal a non-uniform abundance pattern for elements $Z\leq47$. Based on non-correlation trends between elemental abundances as a function of Eu-richness in a large sample…

The rapid neutron-capture process, or r-process, is known to be fundamental for explaining the origin of approximately half of the A>60 stable nuclei observed in nature. In recent years nuclear astrophysicists have developed more and more…

Solar and Stellar Astrophysics · Physics 2015-05-28 S. Goriely , N. Chamel , H. -T. Janka , J. M. Pearson

We study the evolution of Eu and Ba abundances in local group dwarf spheroidal and ultra faint dwarf galaxies by means of detailed chemical evolution models and compare our results with new sets of homogeneous abundances. The adopted models…

The abundance of about half of the stable nuclei heavier than iron via the rapid neutron capture process or $r$-process is intimately related to the competition between neutron capture and $\beta$-decay rates, which ultimately depends on…

High Energy Astrophysical Phenomena · Physics 2021-10-05 José Nicolás Orce , Balaram Dey , Cebo Ngwetsheni , Srijit Bhattacharya , Deepak Pandit , Brenden Lesch , Andile Zulu

Abundance observations indicate the presence of often surprisingly large amounts of neutron capture (i.e., s- and r-process) elements in old Galactic halo and globular cluster stars. These observations provide insight into the nature of the…

Context. In recent years, the R-Process Alliance (RPA) has conducted a successful search for stars enhanced in elements produced by the rapid neutron-capture (r-)process. In particular, the RPA has uncovered a number of stars strongly…

We present a comprehensive nucleosynthesis study of the neutrino-driven wind in the aftermath of a binary neutron star merger. Our focus is the initial remnant phase when a massive central neutron star is present. Using tracers from a…

Solar and Stellar Astrophysics · Physics 2015-10-23 Dirk Martin , Albino Perego , Almudena Arcones , Friedrich-Karl Thielemann , Oleg Korobkin , Stephan Rosswog

Most heavy elements beyond the iron peak are synthesized via neutron capture processes. The nature of the astrophysical sites of neutron capture processes is still very unclear. In this work we explore the observational constraints of the…

Solar and Stellar Astrophysics · Physics 2023-09-25 Jianhui Lian , Nicholas Storm , Guillaume Guiglion , Aldo Serenelli , Benoit Cote , Amanda I. Karakas , Nick Boardman , Maria Bergemann

The s-process in massive stars, producing nuclei up to $A\approx 90$, has a different behaviour at low metallicity if stellar rotation is significant. This enhanced s-process is distinct from the s-process in massive stars around solar…

Solar and Stellar Astrophysics · Physics 2018-02-19 N. Nishimura , R. Hirschi , T. Rauscher

We study the efficiency and sensitivity of r-process nucleosynthesis to 18 light-element nuclear reaction rates. We adopt empirical power-law relations to parameterize the reaction sensitivities. We utilize two different hydrodynamic models…

Astrophysics · Physics 2016-08-30 T. Sasaqui , T. Kajino , G. J. Mathews , K. Otsuki , K. Nakamura

The rapid nuetron-capture process (r process) produces roughly half of the elements heavier than iron. The path and abundances produced are uncertain, however, because of the lack of nuclear strucure information on important neutron-rich…

In a brief review of abundances neutron-capture elements (Z > ~30) in metal-poor halo stars, attention is called to their star-to-star scatter, the dominance of r-process synthesis at lowest metallicities, the puzzle of the lighter members…

Astrophysics · Physics 2016-11-03 C. Sneden , J. J. Cowan , J. W. Truran

Quadrupole transition densities in neutron-rich nuclei in the vicinity of the neutron drip-line are calculated in the framework of the Random Phase Approximation. The continuum is treated by expansion in oscillator functions. We focus on…

Nuclear Theory · Physics 2009-10-30 F. Catara , E. G. Lanza , M. A. Nagarajan , A. Vitturi

Neutron-capture elements, those with Z > 35, are the least well-understood in terms of nucleosynthesis and formation environments. The rapid neutron-capture, or r-process, elements are formed in the environments and/or remnants of massive…

Solar and Stellar Astrophysics · Physics 2016-06-22 Jamie C. Overbeek , Eileen D. Friel , Heather R. Jacobson

We examine the Pb and Th abundances in 27 metal-poor stars (-3.1 < [Fe/H] < -1.4) whose very heavy metal (Z > 56) enrichment was produced only by the rapid (r-) nucleosynthesis process. New abundances are derived from HST/STIS, Keck/HIRES,…

Solar and Stellar Astrophysics · Physics 2011-02-11 Ian U. Roederer , Karl-Ludwig Kratz , Anna Frebel , Norbert Christlieb , Bernd Pfeiffer , John J. Cowan , Christopher Sneden

Nuclear beta decay rates are an essential ingredient in simulations of the astrophysical r-process. Most of these rates still rely on theoretical modeling. However, modern radioactive ion-beam facilities have allowed to measure beta half…

Nuclear Theory · Physics 2014-05-02 O. L. Caballero , A. Arcones , I. N. Borzov , K. Langanke , G. Martinez-Pinedo

(Abridged) It is shown that a semi-quantitative agreement with the gross solar r-process abundance pattern near and above mass number A=130 can be obtained by a superposition of two distinctive kinds of supernova r-process events. These…

Astrophysics · Physics 2009-10-30 Y. -Z. Qian , P. Vogel , G. J. Wasserburg

We study the big-bang nucleosynthesis (BBN) scenario with late-decaying exotic particles with lifetime longer than $\sim 1$ sec. With a late-decaying particle in the early universe, predictions of the standard BBN scenario can be…

Astrophysics · Physics 2010-04-05 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi

The astrophysical site(s) of the r-process are uncertain, with candidates such as neutron star mergers and magneto-rotational supernovae predicting different event rates, delay times, and heavy-element yields. Galactic chemical evolution…

Astrophysics of Galaxies · Physics 2026-05-27 M. Molero , A. Arcones , F. Montes , C. J. Hansen

Exploring nucleon drip lines and astrophysical rapid neutron capture process (r-process) paths in the nuclear landscape is extremely challenging in nuclear physics and astrophysics. While various models predict similar proton drip line,…

Nuclear Theory · Physics 2015-10-22 Rui Wang , Lie-Wen Chen
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