奇特核结构与激发的微观研究

Microscopic Study of Structures and Excitations of Exotic Nuclei

原子核是一个从少体到多体过渡的量子体系,展现了很多有趣的集体现象。随着国际上若干大型放射性核束流实验装置的发展,极不稳定奇特核的结构与激发的研究成为当前核物理的前沿热点问题。本工作以形变弱束缚核^(40)Mg为例,基于格点空间连续谱能量密度泛函和自洽的FAM-QRPA对奇特核的基态与激发态跃迁进行了研究。发现弥散的表面密度分布与连续谱对低能共振有很大影响。通过对同位旋矢量偶极激发的研究,说明低能矮共振与巨共振的微观机制有很大差异。此外还进行了大规模拟合,发展针对丰中子核,超重核的新的高精度有效相互作用,以期为相关学科如核天体物理、核裂变能等提供更为可靠的核理论模型。

Nuclei are quantum systems in the evolution from few-body to many-body systems, and can exhibit many amazing collective phenomena. With the development of several advanced radioactive-beam facilities, the study of structures and excitations of extreme unstable exotic nuclei has become a hot issue. In this work, we solve the self-consistent FAM-QRPA in large deformed coordinate-spaces to treat continuum effects. We study properties of structures and collective excitations in deformed drip-line nuclei. We found that in weakly bound nuclei 40 Mg, the diffuse surface density and pairing density play an important role in low-lying resonance. Through analysis of deformation-induced K-splitting in isovector dipole modes, we see that pygmy resonances have very different mechanism compared to giant resonances. In addition, large-scale fittings are performed to develop highprecision effective interactions, which will provide more reliable theoretical model for related subjects, such as nuclear astrophysics and nuclear fission energy.