Chaotic Motion of a Nucleon in Heavy Nuclei with Necked-in Shape

In the framework of two-center shell model the nearest neighboring level spacing distribution and spectral rigidity of the nucleon in heavy nuclei are calculated when the shape parameters are changed systematically. Two regions of shape parameter in which the chaotic motion of the nucleon occurs are found. It is shown that the chaotic motion appears not only in the heavy nuclei with oblate shapes but also in prolate ones with a considerable neck, which is quite different from the conclusions of Ref. 2]. Bohigas Giannoni Schmit conjecture is corroborated once again by the good quantum-classical correspondence of nucleonic regular (chaotic) motion. In addition, the present work suggests that nuclear dissipation is shape-dependent,strong dissipation is expected for medium or larger separations, and provides nuclear dissipation with a dynamical understanding.