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Collective multipole excitations in a microscopic relativistic approach

Zhong-yu Ma·A. Wandelt·Nguyen Van Giai·D. Vretenar·P. Ring·Li-gang Cao
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Abstract

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.

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Zhong-yu Ma, A. Wandelt, Nguyen Van Giai, D. Vretenar, P. Ring, Li-gang Cao. 2001-07-03. Collective multipole excitations in a microscopic relativistic approach. https://doi.org/10.1016/s0375-9474(01)01598-6

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