Crossover from vibrational torotational collectivity in heavy nuclei in the shell-model Monte Carloapproach
Crossover from vibrational torotational collectivity in heavy nuclei in the shell-model Monte Carloapproach
复制标题
壳模型蒙特卡罗方法中重核振动旋转集体的交叉
DOI：
10.1103/physrevlett.110.042502
复制
发表时间：
2013
影响因子：
8.6
通讯作者：
Y. Alhassid and H. Nakada
中科院分区：
文献类型：
--
作者：
C. Oezen;Y. Alhassid and H. Nakada
随着中子或质子数量从壳层闭合向中壳层增加，重原子核表现出从振动到旋转集体的交叉，但这种交叉的微观描述一直是一个主要的挑战。我们将壳模型蒙特卡罗方法应用于偶偶钐和钕同位素族，并确定了从振动到旋转集体在低温行为中的交叉的微观特征，其中总自旋和温度。该特征与从实验数据中提取的值吻合较好。我们还计算了这些原子核的态密度，发现它们与实验数据非常吻合。最后，我们根据有限温度Hartree-Fock-Bogoliubov近似计算的总态密度与本然态密度之比定义了一个集体增强因子。发现该增强因子随激发能的衰减与这些原子核中的配对和形状相变有关。
Heavy nuclei exhibit a crossover from vibrational to rotational collectivity as the number of neutrons or protons increases from shell closure towards midshell, but the microscopic description of this crossover has been a major challenge. We apply the shell model Monte Carlo approach to families of even-even samarium and neodymium isotopes and identify a microscopic signature of the crossover from vibrational to rotational collectivity in the low-temperature behavior of, whereis the total spin andis the temperature. This signature agrees well with its values extracted from experimental data. We also calculate the state densities of these nuclei and find them to be in very good agreement with experimental data. Finally, we define a collective enhancement factor from the ratio of the total state density to the intrinsic state density as calculated in the finite-temperature Hartree-Fock-Bogoliubov approximation. The decay of this enhancement factor with excitation energy is found to correlate with the pairing and shape phase transitions in these nuclei.