Bonn 2010 – wissenschaftliches Programm
HK 35.3: Hauptvortrag
Mittwoch, 17. März 2010, 09:30–10:00, HG X
Multi-reference energy density functional theory: The description and role of fluctuations in collective degrees of freedom models of nuclear structure based on self-consistent mean fields — •Michael Bender — Centre d'Etudes Nucleaires de Bordeaux Gradignan, France
At present, methods based on self-consistent mean-field approaches are the only microscopic nuclear structure models that can be applied to all nuclei but the very lightest ones irrespective of their mass and neutron-to-proton ratio. Within this framework, a universal effective interaction set-up in the form of an energy density functional of Skyrme, Gogny, relativistic mean-field, or other type, provides a simultaneous description of bulk properties and many features of the excitation spectrum. This presentation will discuss for which nuclides, observables, and phenomena it is advantageous, even necessary, "to go beyond the self-consistent mean field", taking into account correlations that originate in fluctuations of a finite-size system in collective degrees of freedom through the restoration of symmetries and configuration mixing in the framework of the Generator Coordinate Method. The current state-of-the-art will be illustrated for two examples. One is the spectrum of excited collective states and their transition moments of nuclei in the neutron-deficient Pb region exhibiting multiple shape coexistence, the other is the systematics of masses and mass differences of even-even nuclei. An outlook will sketch necessary and/or desirable further developments.