Collective and broken pair states of ${}^{65,67}$Ga

Excited states of ${}^{65}\mathrm{Ga}$ and ${}^{67}\mathrm{Ga}$ nuclei were populated through the ${}^{12}\mathrm{C}{(}^{58}\mathrm{Ni},\alpha p)$ and ${}^{12}\mathrm{C}{(}^{58}\mathrm{Ni},3p)$ reactions, respectively, and investigated by in-beam $\gamma$-ray spectroscopic methods. The NORDBALL array equipped with a charged particle ball and 11 neutron detectors was used to detect the evaporated particles and $\gamma$ rays. The level schemes of ${}^{65,67}\mathrm{Ga}$ were constructed on the basis of $\gamma \gamma$-coincidence relations up to 8.6 and 10 MeV excitation energy, and $I^{\pi }=27/2\mathrm{}$ and ${33/2}^{+}$ spin and parity, respectively. The structure of ${}^{65,67}\mathrm{Ga}$ nuclei was described in the interacting boson-fermion plus broken pair model, including quasiproton, quasiproton-two-quasineutron, and three-quasiproton fermion configurations in the boson-fermion basis states. Most of the states were assigned to quasiparticle + phonon and three quasiparticle configurations on the basis of their electromagnetic decay properties.