Further monopole effects in neutron-rich Sb isotopes* *Research at ZSTU is supported by the National Natural Science Foundation of China (U2267205). Research at IMP is supported by the National Natural Science Foundation of China (U2032211, 12075287). Research at SJTU is supported by the China and Germany Postdoctoral Exchange Fellowship Program 2019 from the office of China Postdoctoral Council (20191024)

Abstract

The level spectra of neutron-rich Sb isotopes have been investigated within a shell-model space containing cross-shell excitations and the intruder orbit . High-spin levels (27/2 ) and (29/2 ) in Sb are taken over by the monopole effect induced by orbit . The ground state and excited levels in Sb are well improved by considering the monopole correction between neutron orbits and . The energy shrinking of the first excited state 5/2 in Sb isotopes is explained by the shift due to the attractive monopole interaction when increasingly more neutrons occupy orbit . The ground state of Sb is predicted as 5/2 owing to the shrinking of the 5/2 states in Sb isotopes that causes ground state inversion when N = 88. Further monopole effects extend the applicable range of the present Hamiltonian to nuclei with more neutrons above the N = 82 shell. This Hamiltonian will be public, and researchers are encouraged to contact the authors.