Quasiparticle time blocking approximation in coordinate space as a model for the damping of the giant dipole resonance
Abstract
The quasiparticle time blocking approximation (QTBA) is presented as a model for the description of naturalparity excitations in openshell nuclei. Most attention is paid to the question of the damping of the giant dipole resonance. Within the model pairing correlations, twoquasiparticle (2q), and 2qxphonon configurations are included. Thus the QTBA is an extension of the quasiparticle random phase approximation to include quasiparticlephonon coupling. Calculational formulas are presented for the case of neutral naturalparity excitations in spherical nuclei. The main equations are written in the coordinate representation that allows to take into account singleparticle continuum completely. The QTBA is applied to describe E1 photoabsorption cross sections in nuclei {sup 116,120,124}Sn. It has been obtained that the 2q(multiplyincircle sign)phonon configurations provide noticeable fragmentation of the giant dipole resonance resulting in the appearance of a significant spreading width. The results are compared with available experimental data.
 Authors:
 Institute of Physics and Power Engineering, RU249033 Obninsk (Russian Federation)
 (Germany)
 Nuclear Physics Department, V. A. Fock Institute of Physics, St. Petersburg State University, RU198504 St. Petersburg (Russian Federation)
 Publication Date:
 OSTI Identifier:
 20995280
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevC.75.054318; (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; CHANNELING; CROSS SECTIONS; DIPOLES; EXCITATION; PARITY; PHONONS; RANDOM PHASE APPROXIMATION; RESONANCE; SPHERICAL CONFIGURATION; TIN 116; TIN 120; TIN 124
Citation Formats
Litvinova, E. V., PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching, and Tselyaev, V. I. Quasiparticle time blocking approximation in coordinate space as a model for the damping of the giant dipole resonance. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVC.75.054318.
Litvinova, E. V., PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching, & Tselyaev, V. I. Quasiparticle time blocking approximation in coordinate space as a model for the damping of the giant dipole resonance. United States. doi:10.1103/PHYSREVC.75.054318.
Litvinova, E. V., PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching, and Tselyaev, V. I. Tue .
"Quasiparticle time blocking approximation in coordinate space as a model for the damping of the giant dipole resonance". United States.
doi:10.1103/PHYSREVC.75.054318.
@article{osti_20995280,
title = {Quasiparticle time blocking approximation in coordinate space as a model for the damping of the giant dipole resonance},
author = {Litvinova, E. V. and PhysikDepartment der Technischen Universitaet Muenchen, D85748 Garching and Tselyaev, V. I.},
abstractNote = {The quasiparticle time blocking approximation (QTBA) is presented as a model for the description of naturalparity excitations in openshell nuclei. Most attention is paid to the question of the damping of the giant dipole resonance. Within the model pairing correlations, twoquasiparticle (2q), and 2qxphonon configurations are included. Thus the QTBA is an extension of the quasiparticle random phase approximation to include quasiparticlephonon coupling. Calculational formulas are presented for the case of neutral naturalparity excitations in spherical nuclei. The main equations are written in the coordinate representation that allows to take into account singleparticle continuum completely. The QTBA is applied to describe E1 photoabsorption cross sections in nuclei {sup 116,120,124}Sn. It has been obtained that the 2q(multiplyincircle sign)phonon configurations provide noticeable fragmentation of the giant dipole resonance resulting in the appearance of a significant spreading width. The results are compared with available experimental data.},
doi = {10.1103/PHYSREVC.75.054318},
journal = {Physical Review. C, Nuclear Physics},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}

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