Establish reliable cluster-emission predictions for odd-mass neutron-rich nuclei

Establish whether the analytical cluster-emission half-life predictions for odd-mass nuclei in the neutron-rich region are reliable, accounting for the shell, pairing, and residual-nucleus effects that can strongly hinder individual decay channels.

Background

The r-process reaction network includes both even- and odd-mass nuclei, but the four formulas used in the paper describe cluster emission through alpha-decay-like barrier penetration and do not explicitly capture all microscopic nuclear-structure effects.

The authors emphasize that odd-mass decays may be strongly hindered by the structure of the residual nucleus, while fully microscopic calculations are unavailable for the thousands of neutron-rich nuclei required by r-process networks. Consequently, the reliability of the calculated rates for individual odd-mass nuclei remains unresolved.

References

Therefore, while the cluster emission half-lives will be calculated for a nuclear network of both even- and odd-$A$ nuclei, it is unclear whether the results for each odd-$A$ nucleus are reliable, as individual shell and pairing effects can have a severe impact on which emissions of a cluster will occur in reality.

— Cluster emission and its impact on the r-process nucleosynthesis  (2608.24499 - Thomas et al., 25 Aug 2026) in Section 2.1, “Half-life models and calculation framework”

However, regarding the neutron-rich side of the nuclear chart, there is no knowledge on whether the improvement holds in this different region.

— Cluster emission and its impact on the r-process nucleosynthesis  (2608.24499 - Thomas et al., 25 Aug 2026) in Section 3.2, “Cluster emission half-lives of the nuclear network”