Quasiparticle time blocking approximation in coordinate space as a model for the damping of the giant dipole resonance
- Institute of Physics and Power Engineering, RU-249033 Obninsk (Russian Federation)
- Nuclear Physics Department, V. A. Fock Institute of Physics, St. Petersburg State University, RU-198504 St. Petersburg (Russian Federation)
The quasiparticle time blocking approximation (QTBA) is presented as a model for the description of natural-parity excitations in open-shell nuclei. Most attention is paid to the question of the damping of the giant dipole resonance. Within the model pairing correlations, two-quasiparticle (2q), and 2qxphonon configurations are included. Thus the QTBA is an extension of the quasiparticle random phase approximation to include quasiparticle-phonon coupling. Calculational formulas are presented for the case of neutral natural-parity excitations in spherical nuclei. The main equations are written in the coordinate representation that allows to take into account single-particle 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(multiply-in-circle 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.
- OSTI ID:
- 20995280
- Journal Information:
- Physical Review. C, Nuclear Physics, Vol. 75, Issue 5; Other Information: DOI: 10.1103/PhysRevC.75.054318; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2813
- Country of Publication:
- United States
- Language:
- English
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