Truncation Effects in the Shell-model Calculations at Neutron-rich Hole Nuclei Close to ¹³²Sn

With two different truncations, i.e., neutron core-excitation truncation and orbital particle-number truncation, the research is studied at the truncation effects in shell-model calculations by the hole nuclei of ¹³⁰Sn, ¹³¹Sn, ¹³⁰In, ¹³⁰In and ¹³⁰Cd. We found that the right ground state of ¹³⁰In needs proton core-excitation in shell model space, and allowing two neutron core-excitations will promote the low-lying states in ¹³²Sn. The neutron core-excitations will also slightly affect the low-lying levels of hole-nuclei close to ¹³²Sn, and the values of BE2 between the corresponded low-lying states reflect more obviously to the neutron core-excitations.