Decay dynamics of the unbound $^{25}$O and $^{26}$O nuclei
Decay dynamics of the unbound $^{25}$O and $^{26}$O nuclei
复制标题
未结合 $^{25}$O 和 $^{26}$O 核的衰变动力学
DOI：
10.1103/physrevc.93.034330
复制
发表时间：
2016
期刊：
影响因子：
--
通讯作者：
H. Sagawa
中科院分区：
文献类型：
--
作者：
K. Hagino;H. Sagawa
我们用三体模型$^{24}$O+n+n研究了$^{26}$O的基态和激发共振态，并考虑了与连续介质的耦合.为此，我们使用新的实验数据的非束缚$^{25}$O和$^{26}$O核的不变质量谱，并提出了一个更新的三体模型计算的两个中子衰变的$^{26}$O核。利用由基态衰变$^{26}$O确定的新模型输入，我们讨论了该核的双电子关联和晕的性质，以及激发态的结构。对于2$^+$态的能量，我们的计算结果与实验数据吻合得很好。我们证明了2$^+$态主要由$（d_{3/2}）^2$组态组成，此时价中子之间的配对相互作用使其能量比未微扰态略有降低。我们还讨论了$^{26}$O核0$^+$激发态的结构.特别地，我们发现在3.38 MeV处存在一个激发态0$^+$，它主要由$（f_{7/2}）^2$组态组成.
We study the ground and excited resonance states of $^{26}$O with a three-body model of $^{24}$O+n+n taking into account the coupling to the continuum. To this end, we use the new experimental data for the invariant mass spectroscopy of the unbound $^{25}$O and $^{26}$O nuclei, and present an update of three-body model calculations for the two-neutron decay of the $^{26}$O nucleus. With the new model inputs determined with the ground state decay of $^{26}$O, we discuss the di-neurtron correlations and a halo nature of this nucleus, as well as the structure of the excited states. For the energy of the 2$^+$ state, we achieve an excellent agreement with the experimental data with this calculation. We show that the 2$^+$ state consists predominantly of the $(d_{3/2})^2$ configuration, for which the pairing interaction between the valence neutrons slightly decreases its energy from the unperturbed one. We also discuss the structure of excited 0$^+$ states of the $^{26}$O nucleus. In particular, we show the existence of an excited 0$^+$ state at 3.38 MeV, which is mainly composed of the $(f_{7/2})^2$ configuration.