Many-Particle and Many-Hole States in Neutron-Rich Ne Isotopes Related to Broken N=20 Shell Closure
نویسندگان
چکیده
The low-lying level structures of Ne, Ne and Ne which are related to the breaking of the N=20 shell closure have been studied by the framework of the deformed-basis antisymmetrized molecular dynamics plus generator coordinate method using Gogny D1S force. The properties of the many-particle and many-hole states are discussed as well as that of the ground band. We predict that the negative-parity states in which neutrons are promoted into pf -orbit from sd orbit have the small excitation energy in the cases of Ne and Ne which, we regard, is a typical phenomena accompanying the breaking of N=20 shell closure. It is also found that the neutron 4p4h structure of Ne appears in low excitation energy which contains α+O correlations. 1 typeset using PTPTEX.cls 〈Ver.0.9〉
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