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

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The determination of astrophysical reaction rates requires different approaches depending on the conditions in hydrostatic and explosive burning. The focus here is on astrophysical reaction rates for radiative neutron capture reactions.…

Nuclear Theory · Physics 2022-11-10 Thomas Rauscher

Heavy quarks, namely, the top and bottom quarks, may show great sensitiveness to new physics effects. In particular, they might have unusually large electric dipole moments. This possibility is analyzed via the corresponding one-loop…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Cordero-Cid , J. M. Hernandez , G. Tavares-Velasco , J. J. Toscano

The conditions for the leading r-process site candidate, neutrino-driven winds, can not be reproduced self-consistently in current supernova models. For that reason, we investigate an alternate model involving the mass ejected by fallback…

Astrophysics · Physics 2009-11-11 Chris L. Fryer , Falk Herwig , Aimee Hungerford , Frank Timmes

We present results from the first large-scale survey of neutron(n)-capture element abundances in planetary nebulae (PNe). This survey was motivated by the fact that a PN may be enriched in n-capture elements if its progenitor star…

Astrophysics · Physics 2007-08-10 N. C. Sterling , Harriet L. Dinerstein , T. R. Kallman

We present a new nucleosynthesis process, that we denote nu p-process, which occurs in supernovae (and possibly gamma-ray bursts) when strong neutrino fluxes create proton-rich ejecta. In this process, antineutrino absorptions in the…

Baryon density inhomogeneities in the early universe can give rise to a floor of heavy elements (up to $A\approx 270$) produced in a primordial r-process with fission cycling. A parameter study with variation of the global baryon to photon…

High Energy Astrophysical Phenomena · Physics 2015-04-20 T. Rauscher , J. H. Applegate , J. J. Cowan , F. -K. Thielemann , M. Wiescher

In past decades a lot of progress has been made towards understanding the main s-process component that takes place in thermally pulsing Asymptotic Giant Branch (AGB) stars. During this process about half of the heavy elements, mainly…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 M. Heil , A. Juseviciute , F. Kaeppeler , R. Gallino , M. Pignatari , E. Uberseder

Densities from relativistic mean field calculations are applied to construct the optical potential and, hence calculate the endpoint of the rapid proton capture ($rp$) process. Mass values are taken from a new phenomenological mass formula.…

Nuclear Theory · Physics 2012-07-30 Chirashree Lahiri , G. Gangopadhyay

The neutron-drip transition in the dense matter constituting the interior of neutron stars generally refers to the appearance of unbound neutrons as the matter density reaches some threshold density $\rho_\textrm{drip}$. This transition has…

High Energy Astrophysical Phenomena · Physics 2015-05-27 N. Chamel , A. F. Fantina , J. L. Zdunik , P. Haensel

The isotopic abundances of r-process elements in the solar system are traditionally derived as residuals from the subtraction of s-process contributions from total solar abundances. However, the uncertainties in s-process nucleosynthesis --…

Nuclear Experiment · Physics 2026-02-03 C. Domingo-Pardo , C. Lederer-Woods , A. Mengoni

Neutron capture cross-sections have been calculated in nuclei near the N=82 neutron shell closure. These nuclei are of astrophysical interest, participating in s-process and p-process. A semi-microscopic optical model have been used with…

Nuclear Theory · Physics 2018-06-19 Saumi Dutta , Dipti Chakraborty , G. Gangopadhyay , Abhijit Bhattacharyya

There are many candidate sites of the r-process: core-collapse supernovae (including rare magnetorotational core-collapse supernovae), neutron star mergers, and neutron star/black hole mergers. The chemical enrichment of…

Astrophysics of Galaxies · Physics 2018-12-19 Gina E. Duggan , Evan N. Kirby , Serge M. Andrievsky , Sergey A. Korotin

We investigated the impact of uncertainties in neutron-capture and weak reactions (on heavy elements) on the s-process nucleosynthesis in low-mass stars and massive stars using a Monte-Carlo based approach. We performed extensive nuclear…

Solar and Stellar Astrophysics · Physics 2017-12-19 G. Cescutti , N. Nishimura , R. Hirschi , T. Rauscher , J. W. den Hartogh , A. St. J. Murphy

Ground- and space-based observations of stellar heavy element abundances are providing a clearer picture of the chemical evolution of the Galaxy. A large number of (r)apid and (s)low neutron capture process elements, including the first…

Astrophysics · Physics 2007-05-23 John J Cowan , Christopher Sneden , James W Truran , Debra L Burris

During the merger of a black hole and a neutron star, baryonic mass can become unbound from the system. Because the ejected material is extremely neutron-rich, the r-process rapidly synthesizes heavy nuclides as the material expands and…

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 2018-03-20 M. Bhuyan

We study effects of long-lived massive particles, which decay during the big-bang nucleosynthesis (BBN) epoch, on the primordial abundances of light elements. Compared to the previous studies, (i) the reaction rates of the standard BBN…

High Energy Physics - Phenomenology · Physics 2018-12-04 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Yoshitaro Takaesu

We reexamine big bang nucleosynthesis with large-scale baryon density inhomogeneities when the length scale of the density fluctuations exceeds the neutron diffusion length ($\sim 10^7-10^8$ cm at BBN), and the amplitude of the fluctuations…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 John D. Barrow , Robert J. Scherrer

Studies aiming to determine the astrophysical origins of nuclei produced by the rapid neutron capture process ($r$ process) rely on nuclear properties as inputs for simulations. The solar abundances can be used as a benchmark for such…

Standard Big Bang Nucleosynthesis at the baryon density determined by the microwave anisotropy spectrum predicts an excess of \li7 compared to observations by a factor of 4-5. In contrast, BBN predictions for D/H are somewhat below (but…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Keith A. Olive , Patrick Petitjean , Elisabeth Vangioni , Joseph Silk
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