Impact of nuclearβ-decay rates on the r-process rare-earth peak abundances

The impact of n-decay rates of an individual nucleus on the r-process rare-earth peak abundances has been studied in different astrophysical scenarios. The variation in n-decay rates by a factor of 10 can produce large abundance uncertainties in the rare-earth mass region, while fission deposition can significantly reduce this uncertainty, which is not a suggested case by the current simulations of neutron-star mergers with moderately neutron-rich conditions where fission is less active. The most impactful nuclei include even-neutron-number (N) nuclei on the early r-process equilibrium path or r-process freeze-out path and nuclei with N = 100, 102, and 104. It is found that the variations in the n-decay rate of nuclei located to the left and right sides of the r-process freeze-out path have significant different effects on rare-earth peak abundance.