论文标题
断裂的轴向对称性是重核中各种可观察力的一致建模的必不可少的特征
Broken axial symmetry as essential feature for a consistent modelling of various observables in heavy nuclei
论文作者
论文摘要
尽管大多数核光谱以及原子超细结构数据并未提供有关核轴向性的准确信息，但在核模型计算中发现对称对称性的临时假设。在对核性质的理论解释以及在实验数据的分析中，仅考虑到某些（通常是外来）核素的三轴性。轴向对称性的破裂结合到惯性的自旋无关时刻，导致所有重核（包括良好变形的核）中yrast序列的简单简单的启发式三轴参数化。在详细研究巨大偶极子共振范围内和外部的电偶极强度的质量和电荷依赖性时，不需要额外的拟合参数。允许三轴性还避免引入任意水平的密度参数ā以符合N捕捉实验中观察到的准确值，并且可以从核物质研究中获取。该值与yrast能量的组合不再基于轴向性和相关的i（i+1）规则结果，而与自旋无关的数据一致。以及基于非轴性衍生的辐射中子捕获的预测也得到了改善。实验中有利于骨折的轴向对称性与HFB和MC-shell模型计算相一致。
Although most nuclear spectroscopy as well as atomic hyperfine structure data do not deliver accurate information on nuclear axiality the ad-hoc assumption of symmetry about one axis found widespread use in nuclear model calculations. In the theoretical interpretation of nuclear properties as well as in the analysis of experimental data triaxiality was considered - if at all - only for some, often exotic, nuclides. A breaking of axial symmetry combined to a spin-independent moment of inertia results in a surprisingly simple heuristic triaxial parametrization of the yrast sequence in all heavy nuclei, including well deformed ones. No additional fit parameters are needed in detailed studies of the mass and charge dependence of the electric dipole strength in the range of and outside of giant dipole resonances. Allowing triaxiality also avoids the introduction of an arbitrary level density parameter ā to fit the accurate values observed in n-capture experiments and ā can be taken from nuclear matter studies. A combination of this value to the yrast energies no longer based on axiality and the related I(I+1) rule results in agreement to data independent of spin. And predictions for radiative neutron capture as derived on the basis of non-axiality are improved as well. The experimentally favoured broken axial symmetry is in accord to HFB and MC-shell model calculations already for nuclei in the valley of stability.
