Photodisintegration of 80Se: Implications for the s-process branching at 79Se

Photoneutron cross sections were measured for $^{80}\mathrm{Se}$ immediately above the neutron separation energy with quasimonochromatic $\ensuremath{\gamma}$-ray beams to experimentally constrain the $E1$ $\ensuremath{\gamma}$ strength function for $^{80}\mathrm{Se}$. Two sets of the $\ensuremath{\gamma}$ strength function and the level density that equally meet the experimental constraint predict largely different neutron capture cross sections for $^{79}\mathrm{Se}$. Based on the Maxwellian-averaged cross sections of the latest compilation complemented with the predicted cross sections for $^{79}\mathrm{Se}$, we calculated $\ensuremath{\sigma}N$ values of the main $s$-process component using a phenomenological model and deduced empirical abundances of the weak $s$-process component. An attempt is made of considering the implications of the abundance ratios of $^{80}\mathrm{Kr}$ and $^{82}\mathrm{Kr}$ within the framework of phenomenological models for the weak $s$ process.