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

200 papers

The framework for the interpretation of neutron-capture elements observed in Population II stars, established 20-25 years ago, is that these stars primarily exhibit r-process signatures, due to the inefficiency of the s-process at low…

Astrophysics · Physics 2009-11-07 Sean G. Ryan

It is shown that the large density fluctuations appearing at the onset of the first order nuclear liquid-gas phase transition can play an important role in the supernovae evolution. Due to these fluctuations, the neutrino gas may be trapped…

Astrophysics · Physics 2009-11-10 Jerome Margueron , Jesus Navarro , Patrick Blottiau

The rapid neutron capture or 'r process' of nucleosynthesis is believed to be responsible for the production of approximately half the natural abundance of heavy elements found on the periodic table above iron (with proton number $Z=26$)…

Nuclear Theory · Physics 2023-04-05 E. M. Holmbeck , T. M. Sprouse , M. R. Mumpower

The $\beta$-decay half-lives of neutron-rich nuclei with $20 \leqslant Z \leqslant 50$ are systematically investigated using the newly developed fully self-consistent proton-neutron quasiparticle random phase approximation (QRPA), based on…

Nuclear Theory · Physics 2013-05-27 Z. M. Niu , Y. F. Niu , H. Z. Liang , W. H. Long , T. Nikšić , D. Vretenar , J. Meng

Theoretical studies of the nucleosynthesis origin of the heavy elements in our Solar System (S.S.) by the rapid neutron-capture process (r-process) still face the entwined uncertainties in the possible astrophysical scenarios and the…

Solar and Stellar Astrophysics · Physics 2015-06-19 Karl-Ludwig Kratz , Khalil Farouqi , Peter Möller

As the density of matter increases, atomic nuclei disintegrate into nucleons and, eventually, the nucleons themselves disintegrate into quarks. The phase transitions (PT's) between these phases can vary from steep first order to smooth…

Nuclear Theory · Physics 2017-09-29 Veronica Dexheimer , Matthias Hempel , Igor Iosilevskiy , Stefan Schramm

Recent spectroscopic measurements in open clusters younger than the Sun, with [Fe/H]>=0, showed that the abundances of neutron-rich elements have continued to increase in the Galaxy after the formation of the Sun, roughly maintaining a…

Solar and Stellar Astrophysics · Physics 2015-06-03 Enrico Maiorca , Laura Magrini , Maurizio Busso , Sofia Randich , Sara Palmerini , Oscar Trippella

We re-investigate the evolution of the strongly degenerate neutrinos in the early universe. With the larger degeneracy, the neutrino number freezes at higher temperatures because the neutrino annihilation rate decreases. We consider very…

Astrophysics · Physics 2009-11-07 Kazuhide Ichikawa , M. Kawasaki

The fluctuation properties of nuclear giant resonance spectra are studied in the presence of continuum decay. The subspace of quasi-bound states is specified by one-particle one-hole and two-particle two-hole excitations and the continuum…

Nuclear Theory · Physics 2009-01-23 S. Drożdż , A. Trellakis , J. Wambach

Uncertainties in nuclear models have a major impact on simulations that aim at understanding the origin of heavy elements in the universe through the rapid neutron capture process ($r$ process) of nucleosynthesis. Within the framework of…

Nuclear Theory · Physics 2020-05-20 T. M. Sprouse , R. Navarro Perez , R. Surman , M. R. Mumpower , G. C. McLaughlin , N. Schunck

The astrophysical origin of the rapid neutron-capture process (r-process), which produces about half of the elements heavier than iron, remains uncertain. The oldest, most metal-poor stars preserve the chemical signatures of early…

The ability to now make measurements of Be and B as well as put constraints on \lisix\ abundances in metal-poor stars has led to a detailed reexamination of Big Bang Nucleosynthesis in the $A\groughly6$ regime. The nuclear reaction network…

Astrophysics · Physics 2009-09-15 David Thomas , David N. Schramm , Keith A. Olive , Brian D. Fields

The relic abundances of the light elements synthesized during the first few minutes of the evolution of the Universe provide unique probes of cosmology and the building blocks for stellar and galactic chemical evolution, while also enabling…

Astrophysics · Physics 2015-06-24 Gary Steigman

We study the role of light neutron-rich nuclei during r-process nucleosynthesis in supernovae. Most previous studies of the r-process have concentrated on the reaction flow of heavy unstable nuclei. Although the nuclear reaction network…

Astrophysics · Physics 2009-11-06 M. Terasawa , K. Sumiyoshi , T. Kajino , G. J. Mathews , I. Tanihata

The astrophysical p-process is responsible for the origin of the proton rich nuclei,which are heavier than iron. A huge network involving thousands of reaction rates is necessary to calculate the final p-abundances. But not all rates…

Astrophysics · Physics 2009-11-10 W. Rapp , M. Wiescher , H. Schatz , F. Käppeler

Resonance trapping appears in open many-particle quantum systems at high level density when the coupling to the continuum of decay channels reaches a critical strength. Here a reorganization of the system takes place and a separation of…

Nuclear Theory · Physics 2011-03-15 E. Persson , T. Gorin , I. Rotter

Whereas light element abundance variations are a hallmark of globular clusters, there is little evidence for variation in neutron-capture elements. A significant exception is M15, which shows a star-to-star dispersion in neutron-capture…

Solar and Stellar Astrophysics · Physics 2023-11-17 Evan N. Kirby , Alexander P. Ji , Mikhail Kovalev

The modes of decay for the even-even isotopes of superheavy nuclei of Z = 118 and 120 with neutron number $160 \leq N \leq 204$ are investigated in the framework of the axially deformed relativistic mean field model. The asymmetry parameter…

Nuclear Theory · Physics 2018-05-15 M. Bhuyan , B. V. Carlson

A rudimentary calculation is employed to evaluate the possible effects of beta- decays of excited-state nuclei on the astrophysical r-process. Single-particle levels calculated with the FRDM are adapted to the calculation of beta-decay…

Astrophysics · Physics 2010-11-23 M. A. Famiano , R. N. Boyd , T. Kajino , K. Otsuki , M. Terasawa , G. J. Mathews

In this work we model stationary neutron star envelopes at high accretion rates and describe our new code for such studies. As a first step we put special emphasis on the rp-process which results in the synthesis of heavy elements and study…

High Energy Astrophysical Phenomena · Physics 2024-03-22 Martin Nava-Callejas , Yuri Cavecchi , Dany Page