Fission and the r-process nucleosynthesis of translead nuclei in neutron star mergers

Abstract

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 different ejecta conditions using three sets of stellar reaction rates, one of which is based on microscopic and consistent calculations of nuclear masses, fission barriers, and collective inertias. We show that the accumulation of fissioning material during the r process can strongly affect the free neutron abundance after the r-process freeze-out. This leads to a significant impact on the abundances of heavy nuclei that undergo $\alpha$ decay or spontaneous fission, affecting the radioactive energy production by the ejecta at timescales relevant for kilonova emission.

10 pages, 9 figures

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Cited by in corpus (20)

• Origin of the Heaviest Elements: the Rapid Neutron-Capture Process
• Modeling Kilonova Light Curves: Dependence on Nuclear Inputs
• The Science of the Einstein Telescope
• On the Validity of Steady-State for Nebular Phase Kilonovae
• Nucleosynthesis and observation of the heaviest elements
• r-Process Radioisotopes from Near-Earth Supernovae and Kilonovae
• The Influence of Beta Decay Rates on r-Process Observables
• Impact of systematic nuclear uncertainties on composition and decay heat of dynamical and disk ejecta in compact binary mergers
• Finite-amplitude method for collective inertia in spontaneous fission
• Theoretical description of fission yields: towards a fast and efficient global model
• Potential energy surfaces and fission fragment mass yields of even-even superheavy nuclei
• Actinide signatures in low electron fraction kilonova ejecta
• Cautionary tales on heating-rate prescriptions in kilonovae
• Isochronic evolution and the radioactive decay of r-process nuclei
• Direct Determination of Fission-Barrier Heights Using Light-Ion Transfer in Inverse Kinematics
• Progress in Nuclear Astrophysics of East and Southeast Asia
• Cluster properties of heavy nuclei predicted with the Barcelona-Catania-Paris-Madrid energy density functional
• Nuclear Reactions in Evolving Stars
• Nuclear astrophysics
• Odd nuclei and quasiparticle excitations within the Barcelona Catania Paris Madrid energy density functional