Search for evidence of rotational cluster bands in O18

Le résumé fourni par la source

Clustering in $^{18}\mathrm{O}$ is of great interest to the nuclear physics community, due to theoretical predictions of $\mathrm{core}+\ensuremath{\alpha}$ and nuclear molecular structures. An experiment was performed in order to measure branching ratios for states in $^{18}\mathrm{O}$, determining the tendency towards clustering based on the value of ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\alpha}}/{\mathrm{\ensuremath{\Gamma}}}_{\text{tot}}$ for each state, and the reduced widths compared to the Wigner limit. An experimental method that enables the measurement of branching ratios for almost all available decay modes, including $\ensuremath{\gamma}$ decay, $\ensuremath{\alpha}$ decay, and $n$ decay, was employed. The method is also sensitive to the population of excited states in daughter nuclei, allowing for more accurate determination of the ${\ensuremath{\alpha}}_{0}$ branch. The measurements represent, for several states, either the first branching ratio measurement or the first determination of ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\alpha}}/{\mathrm{\ensuremath{\Gamma}}}_{\text{tot}}$. Based on these measurements, no evidence of consistent cluster structure is seen across any of the bands previously proposed, casting doubt on their existence. Despite this, some states displaying cluster structure are observed.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.