Experimental study of nuclei in the vicinity of the "island of inversion" through the fusion-evaporation reaction

摘要: We report the observation of high-spin states in nuclei vicinity ``island inversion,'' populated via $^{18}\mathrm{O}+^{18}\mathrm{O}$ fusion reaction at an incident beam energy $34$ MeV. The mechanism circumvents limitations other reactions used so far to populate excited these nuclei. level structures $^{33,34}\mathrm{P}$ and $^{33}\mathrm{S}$ have been investigated their schemes were substantially extended. intensities branching ratios $\ensuremath{\gamma}$ transitions measured. observed coincidence intensity anisotropy polarization asymmetry analyzed for a consistent assignment spins parities nuclear levels. $1876$-keV transition $^{34}\mathrm{P}$ that had ambiguous multipolarity has confirmed be mixed transition. Truncated (1p-1h) shell model calculations within ``$\mathit{sdpf}$'' valence space performed. These reproduce experimental excitation energies but fail explain mixing ratio