Collective nuclear excitations with Skyrme-second random-phase approximation

Journal Article · Sat May 15 00:00:00 EDT 2010 · Physical Review. C, Nuclear Physics

DOI:https://doi.org/10.1103/PHYSREVC.81.054312· OSTI ID:21389020

Gambacurta, D; Catara, F ^[1]; Grasso, M ^[2]

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1. Dipartimento di Fisica e Astronomia dell'Universita di Catania, Via S. Sofia 64, I-95123 Catania (Italy)
2. Institut de Physique Nucleaire, Universite Paris-Sud, IN2P3-CNRS, F-91406 Orsay Cedex (France)

Second random-phase approximation (RPA) calculations with a Skyrme force are performed to describe both high- and low-lying excited states in {sup 16}O. The coupling between one particle-one hole and two particle-two hole as well as that between two particle-two hole configurations among themselves are fully taken into account, and the residual interaction is never neglected; we do not resort therefore to a generally used approximate scheme where only the first kind of coupling is considered. The issue of the rearrangement terms in the matrix elements beyond the standard RPA will be considered in detail in a forthcoming paper. Two approximations are employed here for these rearrangement terms: they are either neglected or evaluated with the RPA procedure. As a general feature of second RPA results, a several-MeV shift of the strength distribution to lower energies is systematically found with respect to RPA distributions. A much more important fragmentation of the strength is also naturally provided by the second RPA owing to the huge number of two particle-two hole configurations. A better description of the excitation energies of the low-lying 0{sup +} and 2{sup +} states is obtained with the second RPA than with the RPA.

• OSTI ID: 21389020
• Journal Information: Physical Review. C, Nuclear Physics, Vol. 81, Issue 5; Other Information: DOI: 10.1103/PhysRevC.81.054312; (c) 2010 The American Physical Society; ISSN 0556-2813
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
COMPUTERIZED SIMULATION
CONFIGURATION
COUPLING
DISTRIBUTION
EXCITATION
EXCITED STATES
FRAGMENTATION
MATRIX ELEMENTS
MEV RANGE 01-10
OXYGEN 16
RANDOM PHASE APPROXIMATION
RESIDUAL INTERACTIONS
SKYRME POTENTIAL
APPROXIMATIONS
CALCULATION METHODS
ENERGY LEVELS
ENERGY RANGE
ENERGY-LEVEL TRANSITIONS
EVEN-EVEN NUCLEI
INTERACTIONS
ISOTOPES
LIGHT NUCLEI
MEV RANGE
NUCLEI
NUCLEON-NUCLEON POTENTIAL
OXYGEN ISOTOPES
POTENTIALS
SIMULATION
STABLE ISOTOPES