Investigation of the level structure of 91−94 Zr nuclei using large-scale shell-model calculations*

Abstract A suitable Hamiltonian was designed for the Zr isotopes over the N = 50 shell by including shell model space between 78 Ni and 132 Sn. The Hamiltonian is composed by the pairing-plus-multipole force and monopole correction terms. The single-particle energies (SPEs) were initially taken from the low-lying states of hole nuclei 131 In and 131 Sn (near the N = 82 shell closure). These SPEs were then modified by three monopole correction terms to better describe the low-lying states of 91 Zr (near the N = 50 shell closure). To test this Hamiltonian, the level spectra of 91−94 Zr were investigated in both low-lying and high-spin excitations by large-scale shell-model calculations. Their wave functions were further tested by comparing the electromagnetic transition probabilities with given data. The good performance in both spectra and transitions probabilities makes the predicting calculations of the present interaction more dependable to be referred in further experimental researches of Zr isotopes.