标题： 微观相对论方法中的集体多极激发 显示英文标题

标题： Collective multipole excitations in a microscopic relativistic approach

摘要： 相对论平均场框架下对原子核集体激发的描述是在完全自洽的相对论随机相位近似（RRPA）中进行研究的。 特别是分析了球形原子核中多极巨共振和低能集体态的RRPA计算结果。 通过使用在平均场近似下能够准确描述基态性质的有效拉格朗日量，也发现了低能集体态和巨共振的激发能与实验数据有很好的一致性。 在RRPA成功描述有限核动力学性质方面有两个关键点：（i）在介子部分使用包含非线性项的有效拉格朗日量，（ii）对负能态的狄拉克海进行完全一致的处理。 显示英文摘要

摘要： A relativistic mean field description of collective excitations of atomic nuclei is studied in the framework of a fully self-consistent relativistic random phase approximation (RRPA). In particular, results of RRPA calculations of multipole giant resonances and of low-lying collective states in spherical nuclei are analyzed. By using effective Lagrangians which, in the mean-field approximation, provide an accurate description of ground-state properties, an excellent agreement with experimental data is also found for the excitation energies of low-lying collective states and of giant resonances. Two points are essential for the successful application of the RRPA in the description of dynamical properties of finite nuclei: (i) the use of effective Lagrangians with non-linear terms in the meson sector, and (ii) the fully consistent treatment of the Dirac sea of negative energy states.