Nuclear collective excitations using correlated realistic interactions: The role of explicit randomphase approximation correlations
Abstract
We examine to what extent correlated realistic nucleonnucleon interactions, derived within the unitary correlation operator method (UCOM), can describe nuclear collective motion in the framework of firstorder randomphase approximation (RPA). To this end we employ the correlated Argonne V18 interaction in calculations within the socalled ''Extended'' RPA (ERPA) and investigate the response of closedshell nuclei. The ERPA is a renormalized RPA version which considers explicitly the depletion of the Fermi sea due to longrange correlations and thus allows us to examine how these affect the excitation spectra. It is found that the effect on the properties of giant resonances is rather small. Compared to the standard RPA, where excitations are built on top of the uncorrelated HartreeFock (HF) ground state, their centroid energies decrease by up to 1 MeV, approximately, in the isovector channel. The isoscalar response is less affected in general. Thus, the disagreement between our previous UCOMbased RPA calculations and the experimental data are to be attributed to other effects, namely to residual threebody terms in the Hamiltonian and to higherorder configurations. Singleparticle energies and occupation probabilities obtained within the ERPA are compared with corresponding HF and perturbationtheory results and are discussed as well. The ERPA formalism ismore »
 Authors:
 Institut fuer Kernphysik, Technische Universitaet Darmstadt, Schlossgartenstr. 9, D64289 Darmstadt (Germany)
 Publication Date:
 OSTI Identifier:
 20990949
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevC.75.014310; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; COLLECTIVE EXCITATIONS; GIANT RESONANCE; GROUND STATES; HAMILTONIANS; HARTREEFOCK METHOD; ISOVECTORS; MEV RANGE; NUCLEONNUCLEON INTERACTIONS; PERTURBATION THEORY; RANDOM PHASE APPROXIMATION; THREEBODY PROBLEM
Citation Formats
Papakonstantinou, P., Roth, R., and Paar, N. Nuclear collective excitations using correlated realistic interactions: The role of explicit randomphase approximation correlations. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVC.75.014310.
Papakonstantinou, P., Roth, R., & Paar, N. Nuclear collective excitations using correlated realistic interactions: The role of explicit randomphase approximation correlations. United States. doi:10.1103/PHYSREVC.75.014310.
Papakonstantinou, P., Roth, R., and Paar, N. Mon .
"Nuclear collective excitations using correlated realistic interactions: The role of explicit randomphase approximation correlations". United States.
doi:10.1103/PHYSREVC.75.014310.
@article{osti_20990949,
title = {Nuclear collective excitations using correlated realistic interactions: The role of explicit randomphase approximation correlations},
author = {Papakonstantinou, P. and Roth, R. and Paar, N.},
abstractNote = {We examine to what extent correlated realistic nucleonnucleon interactions, derived within the unitary correlation operator method (UCOM), can describe nuclear collective motion in the framework of firstorder randomphase approximation (RPA). To this end we employ the correlated Argonne V18 interaction in calculations within the socalled ''Extended'' RPA (ERPA) and investigate the response of closedshell nuclei. The ERPA is a renormalized RPA version which considers explicitly the depletion of the Fermi sea due to longrange correlations and thus allows us to examine how these affect the excitation spectra. It is found that the effect on the properties of giant resonances is rather small. Compared to the standard RPA, where excitations are built on top of the uncorrelated HartreeFock (HF) ground state, their centroid energies decrease by up to 1 MeV, approximately, in the isovector channel. The isoscalar response is less affected in general. Thus, the disagreement between our previous UCOMbased RPA calculations and the experimental data are to be attributed to other effects, namely to residual threebody terms in the Hamiltonian and to higherorder configurations. Singleparticle energies and occupation probabilities obtained within the ERPA are compared with corresponding HF and perturbationtheory results and are discussed as well. The ERPA formalism is presented in detail.},
doi = {10.1103/PHYSREVC.75.014310},
journal = {Physical Review. C, Nuclear Physics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}

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