Impact of Nuclear β-decay Half-life Uncertainties on the r-process Simulations

Abstract

The impact of nuclear β -decay half-life uncertainties on the r -process simulations are investigated in the hot wind r -process scenarios. It is found that the theoretical deviations among various half-life predictions are generally smaller and larger than 1 order of magnitude for the unknown nuclei with N ≲ 126 and N ≳ 126, respectively. This will have a significant impact on the r -process freeze-out time and the neutron-to-seed ratio after the freeze-out time. A universal staggering pattern is observed for the r -process abundances with the use of different half-life models before freeze-out. After the freeze-out, nuclear β -decay half-lives remarkably affect the detailed r -process abundance distributions. It is also found that nuclear β -decay half-lives have a remarkable impact on the abundances of transuranium elements, which play an important role in reproducing the second and the rare-earth peaks of solar r -process abundances, and filling the troughs before them by nuclear fissions.

Keywords

• R-process
• Nucleosynthesis