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Related papers: Neutron capture rates and r-process nucleosynthesi…

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A brief overview of the r-process is given with an emphasis on the observational implications for this process. The conditions required for the major production of the heavy r-process elements (r-elements) with mass numbers A >130 are…

Astrophysics · Physics 2008-09-18 Yong-Zhong Qian

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…

We study the impact of fission on the production and destruction of translead nuclei during the r-process nucleosynthesis occurring in neutron-star mergers. Abundance patterns and rates of nuclear energy production are obtained for…

Nuclear Theory · Physics 2020-10-13 Samuel A. Giuliani , Gabriel Martínez-Pinedo , Meng-Ru Wu , Luis M. Robledo

50% of the heavy element abundances are produced via slow neutron capture reactions in different stellar scenarios. The underlying nucleosynthesis models need the input of neutron capture cross sections. One of the fundamental signatures…

Nuclear astrophysics simulations aiming to study the origin of the elements in stars require a multitude of nuclear physics input. Both systematic model dependent and statistically correlated uncertainties need to be considered. An…

Solar and Stellar Astrophysics · Physics 2013-10-18 M. G. Bertolli , F. Herwig , M. Pignatari , T. Kawano

Electron capture rates on neutron-rich nuclei (A>65) were calculated within the Random Phase Approximation with partial number formalism, including allowed and forbidden transitions. The partial occupation numbers were provided as a…

Nuclear Theory · Physics 2015-06-26 J. M. Sampaio , K. Langanke , G. Martinez-Pinedo , E. Kolbe , D. J. Dean

The r-process in a low temperature environment is explored, in which the neutron emission by photodisintegration does not play a role (cold r-process). A semi-analytic neutrino-driven wind model is utilized for this purpose. The temperature…

Astrophysics · Physics 2009-11-13 Shinya Wanajo

We consider the astrophysical reaction rates for radiative neutron capture reactions ($n,\gamma$) in the crust of a neutron star. The presence of degenerate neutrons at high densities (mainly in the inner crust) can drastically affect the…

Solar and Stellar Astrophysics · Physics 2012-07-26 P. S. Shternin , M. Beard , M. Wiescher , D. G. Yakovlev

We apply Markov Chain Monte Carlo to predict the masses required to form the observed solar $r$-process rare-earth abundance peak. Given highly distinct astrophysical outflows and nuclear inputs, we find that results are most sensitive to…

Nuclear Theory · Physics 2022-02-22 Nicole Vassh , Gail C. McLaughlin , Matthew R. Mumpower , Rebecca Surman

Recent hydrodynamic simulations of core-collapse supernovae with accurate neutrino transport suggest that the bulk of the early neutrino-heated ejecta is proton rich, in which the production of some interesting proton-rich nuclei is…

Astrophysics · Physics 2009-11-11 Shinya Wanajo

We investigate the effects of newly measured beta-decay half-lives on r-process nucleosynthesis. These new rates were determined by recent experiments at the radioactive isotope beam factory facility in the RIKEN Nishina Center. We adopt an…

Solar and Stellar Astrophysics · Physics 2012-04-05 Nobuya Nishimura , Toshitaka Kajino , Grant J. Mathews , Shunji Nishimura , Toshio Suzuki

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

Electron captures on nuclei play an important role in the dynamics of the collapsing core of a massive star that leads to a supernova explosion. Recent calculations of these capture rates were based on microscopic models which account for…

Nuclear Theory · Physics 2010-11-23 A. Juodagalvis , K. Langanke , W. R. Hix , G. Martínez-Pinedo , J. M. Sampaio

Background: The astrophysical $r$-process occurs in an explosive astrophysical event under extremely neutron-rich conditions, leading to (n,$\gamma$)-($\gamma$,n) equilibrium along isotopic chains which peaks around neutron separation…

Nuclear Theory · Physics 2016-09-21 Peter Mohr

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

Solar and Stellar Astrophysics · Physics 2020-01-08 G. Cescutti , R. Hirschi , N. Nishimura , T. Rauscher , J. den Hartogh , A. St. J. Murphy , S. Cristallo

We use the R-matrix theory to fit low-energy data on nuclear reactions involved in Big Bang nucleosynthesis. A special attention is paid to the rate uncertainties which are evaluated on statistical grounds. We provide S factors and reaction…

Reliable nuclear weak rates are key inputs for understanding the origin of heavy elements and constraining the environments of the corresponding stellar nucleosynthesis. We present the effective stellar $\beta^-$-decay rates of the $N=50,…

Nuclear Theory · Physics 2025-09-30 Qi-Ye Hu , Long-Jun Wang , Yang Sun

Deciphering the conditions under which neutron captures occur in the Universe to synthesize heavy elements is an endeavour pursued since the 1950s, but that has proven elusive up to now due to the experimental difficulty of generating the…

Plasma Physics · Physics 2023-12-15 Vojtěch Horný , Sophia N. Chen , Xavier Davoine , Laurent Gremillet , Julien Fuchs

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

Abundance observations indicate the presence of rapid-neutron capture (i.e., r-process) elements in old Galactic halo and globular cluster stars. These observations demonstrate that the earliest generations of stars in the Galaxy,…

Astrophysics · Physics 2017-08-23 J. J. Cowan , C. Sneden