Influence of angular momentum in axially symmetric potentials with octupole deformation

The chaotic classical single-particle motion in an oblate octupole deformed potential with a nonzero z-component of angular momentum Lz is investigated. The stability analysis of the trajectories shows that with increasing rotation of the system, the unstable negative curvature regions of the effective potential surface decrease, which converts the chaotic motion of the system into a regular one.

Analytical description of shape transition in nuclear alternating parity bands

The angular momentum dependencies parity bands of heavy nuclei have been analyzed of parity splitting and electric dipole transitions in the alternating It is shown that these dependencies can be treated in a universal manner with a single critical angular momentum parameter, which characterizes phase transition from octupole vibrations to the stable octupole deformation. Using the simple but useful model of axially-symmetric reflection- asymmetric mode, the analytical expressions for parity splitting and electric dipole transitional moment have been obtained. The findings are in good agreement with the experimental data for various isotopes of Ra, Th, U, and Pu.

单粒子在非轴对称八极形变势场中的混沌运动

针对单粒子处在长椭球谐振子势加上Y32+Y3-2形变势场中的情况,从经典和量子两个角度分析了粒子在非轴对称八极形变势场中的混沌运动．通过经典的轨道稳定性分析,指出了系统等势能面性质对粒子运动特点的重要性．又通过对体系存在的能级免交叉现象,三维不对称谐振子相干态在势场中的演化特征的研究,具体地说明了八级形变势的非轴对称性使单粒子更容易出现混沌运动．

经典粒子在轴对称八极形变势场中的混沌运动

在自然界中长的变形核数目多于扁的变形核数目，这一事实发现与核子的混沌运动有关。经典理论的初步研究表明，粒子在扁椭球加八极形变场中比在长椭球加八极形变场中的运动能在更小的形变参数下产生混沌运动，原因是前者的势能面能在更小的形变参数下出现负曲率。