Particlevibration coupling within covariant density functional theory
Abstract
Covariant density functional theory, which has so far been applied only within the framework of static and timedependent meanfield theory, is extended to include particlevibration coupling (PVC) in a consistent way. Starting from a conventional energy functional, we calculate the lowlying collective vibrations in the relativistic random phase approximation (RRPA) and construct an energydependent selfenergy for the Dyson equation. The resulting BetheSalpeter equation in the particlehole (ph) channel is solved in the time blocking approximation (TBA). No additional parameters are used, and double counting is avoided by a proper subtraction method. The same energy functional, i.e., the same set of coupling constants, generates the DiracHartree singleparticle spectrum, the static part of the residual ph interaction, and the particlephonon coupling vertices. Therefore, a fully consistent description of nuclear excited states is developed. This method is applied for an investigation of damping phenomena in the spherical nuclei with closed shells {sup 208}Pb and {sup 132}Sn. Since the phonon coupling terms enrich the RRPA spectrum with a multitude of phxphonon components, a noticeable fragmentation of the giant resonances is found, which is in full agreement with experimental data and with results of the semiphenomenological nonrelativistic approach.
 Authors:
 PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching (Germany) and Institute of Physics and Power Engineering, RU249033 Obninsk (Russian Federation)
 (Germany)
 (Russian Federation)
 Publication Date:
 OSTI Identifier:
 21003455
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevC.75.064308; (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; BETHESALPETER EQUATION; COLLECTIVE MODEL; COUPLING; DENSITY FUNCTIONAL METHOD; GIANT RESONANCE; LEAD 208; NUCLEAR FRAGMENTATION; PARTICLES; PHONONS; RANDOM PHASE APPROXIMATION; RELATIVISTIC RANGE; SELFENERGY; SHELL MODELS; SPHERICAL CONFIGURATION; TIME DEPENDENCE; TIN 132; VIBRATIONAL STATES
Citation Formats
Litvinova, E., Ring, P., Tselyaev, V., PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching, and Nuclear Physics Department, V.A. Fock Institute of Physics, St. Petersburg State University, RU198504 St. Petersburg. Particlevibration coupling within covariant density functional theory. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVC.75.064308.
Litvinova, E., Ring, P., Tselyaev, V., PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching, & Nuclear Physics Department, V.A. Fock Institute of Physics, St. Petersburg State University, RU198504 St. Petersburg. Particlevibration coupling within covariant density functional theory. United States. doi:10.1103/PHYSREVC.75.064308.
Litvinova, E., Ring, P., Tselyaev, V., PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching, and Nuclear Physics Department, V.A. Fock Institute of Physics, St. Petersburg State University, RU198504 St. Petersburg. 2007.
"Particlevibration coupling within covariant density functional theory". United States.
doi:10.1103/PHYSREVC.75.064308.
@article{osti_21003455,
title = {Particlevibration coupling within covariant density functional theory},
author = {Litvinova, E. and Ring, P. and Tselyaev, V. and PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching and Nuclear Physics Department, V.A. Fock Institute of Physics, St. Petersburg State University, RU198504 St. Petersburg},
abstractNote = {Covariant density functional theory, which has so far been applied only within the framework of static and timedependent meanfield theory, is extended to include particlevibration coupling (PVC) in a consistent way. Starting from a conventional energy functional, we calculate the lowlying collective vibrations in the relativistic random phase approximation (RRPA) and construct an energydependent selfenergy for the Dyson equation. The resulting BetheSalpeter equation in the particlehole (ph) channel is solved in the time blocking approximation (TBA). No additional parameters are used, and double counting is avoided by a proper subtraction method. The same energy functional, i.e., the same set of coupling constants, generates the DiracHartree singleparticle spectrum, the static part of the residual ph interaction, and the particlephonon coupling vertices. Therefore, a fully consistent description of nuclear excited states is developed. This method is applied for an investigation of damping phenomena in the spherical nuclei with closed shells {sup 208}Pb and {sup 132}Sn. Since the phonon coupling terms enrich the RRPA spectrum with a multitude of phxphonon components, a noticeable fragmentation of the giant resonances is found, which is in full agreement with experimental data and with results of the semiphenomenological nonrelativistic approach.},
doi = {10.1103/PHYSREVC.75.064308},
journal = {Physical Review. C, Nuclear Physics},
number = 6,
volume = 75,
place = {United States},
year = 2007,
month = 6
}

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