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Title: Semiclassical approaches to nuclear dynamics

Abstract

The extended Gutzwiller trajectory approach is presented for the semiclassical description of nuclear collective dynamics, in line with the main topics of the fruitful activity of V.G. Solovjov. Within the Fermi-liquid droplet model, the leptodermous effective surface approximation was applied to calculations of energies, sum rules, and transition densities for the neutron–proton asymmetry of the isovector giant-dipole resonance and found to be in good agreement with the experimental data. By using the Strutinsky shell correction method, the semiclassical collective transport coefficients, such as nuclear inertia, friction, stiffness, and moments of inertia, can be derived beyond the quantum perturbation approximation of the response function theory and the cranking model. The averaged particle-number dependences of the low-lying collective vibrational states are described in good agreement with the basic experimental data, mainly due to the enhancement of the collective inertia as compared to its irrotational flow value. Shell components of the moment of inertia are derived in terms of the periodic-orbit free-energy shell corrections. A good agreement between the semiclassical extended Thomas–Fermi moments of inertia with shell corrections and the quantum results is obtained for different nuclear deformations and particle numbers. Shell effects are shown to be exponentially dampted out with increasing temperaturemore » in all the transport coefficients.« less

Authors:
;  [1];  [2]
  1. Institute for Nuclear Research NASU (Ukraine)
  2. Université de Strasbourg, Institut Pluridisciplinaire Hubert Curien, CNRS/IN2P3 (France)
Publication Date:
OSTI Identifier:
22613997
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Atomic Nuclei; Journal Volume: 80; Journal Issue: 1; Other Information: Copyright (c) 2017 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; ASYMMETRY; CORRECTIONS; CRANKING MODEL; DIPOLES; DROPLET MODEL; EXPERIMENTAL DATA; FERMI GAS; FREE ENERGY; GIANT RESONANCE; ISOVECTORS; MOMENT OF INERTIA; NUCLEAR DEFORMATION; PROTON-NEUTRON INTERACTIONS; RESPONSE FUNCTIONS; SEMICLASSICAL APPROXIMATION; SHELL MODELS; SUM RULES; THOMAS-FERMI MODEL; VIBRATIONAL STATES

Citation Formats

Magner, A. G., E-mail: magner@kinr.kiev.ua, Gorpinchenko, D. V., and Bartel, J. Semiclassical approaches to nuclear dynamics. United States: N. p., 2017. Web. doi:10.1134/S1063778817010124.
Magner, A. G., E-mail: magner@kinr.kiev.ua, Gorpinchenko, D. V., & Bartel, J. Semiclassical approaches to nuclear dynamics. United States. doi:10.1134/S1063778817010124.
Magner, A. G., E-mail: magner@kinr.kiev.ua, Gorpinchenko, D. V., and Bartel, J. Sun . "Semiclassical approaches to nuclear dynamics". United States. doi:10.1134/S1063778817010124.
@article{osti_22613997,
title = {Semiclassical approaches to nuclear dynamics},
author = {Magner, A. G., E-mail: magner@kinr.kiev.ua and Gorpinchenko, D. V. and Bartel, J.},
abstractNote = {The extended Gutzwiller trajectory approach is presented for the semiclassical description of nuclear collective dynamics, in line with the main topics of the fruitful activity of V.G. Solovjov. Within the Fermi-liquid droplet model, the leptodermous effective surface approximation was applied to calculations of energies, sum rules, and transition densities for the neutron–proton asymmetry of the isovector giant-dipole resonance and found to be in good agreement with the experimental data. By using the Strutinsky shell correction method, the semiclassical collective transport coefficients, such as nuclear inertia, friction, stiffness, and moments of inertia, can be derived beyond the quantum perturbation approximation of the response function theory and the cranking model. The averaged particle-number dependences of the low-lying collective vibrational states are described in good agreement with the basic experimental data, mainly due to the enhancement of the collective inertia as compared to its irrotational flow value. Shell components of the moment of inertia are derived in terms of the periodic-orbit free-energy shell corrections. A good agreement between the semiclassical extended Thomas–Fermi moments of inertia with shell corrections and the quantum results is obtained for different nuclear deformations and particle numbers. Shell effects are shown to be exponentially dampted out with increasing temperature in all the transport coefficients.},
doi = {10.1134/S1063778817010124},
journal = {Physics of Atomic Nuclei},
number = 1,
volume = 80,
place = {United States},
year = {Sun Jan 15 00:00:00 EST 2017},
month = {Sun Jan 15 00:00:00 EST 2017}
}
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  • For the low-lying collective excitations in nuclei, the transport coefficients, such as the stiffness, the inertia, and the friction, are derived within the periodic-orbit theory in the lowest orders of semiclassical expansion corresponding to the extended Thomas-Fermi approach. The multipole vibrations near the spherical shape are described in the mean-field approximation through the infinitely deep square-well potential and Strutinsky averaging of the transport coefficients. Owing to the consistency condition, the collective inertia for sufficiently increased particle numbers and temperatures is substantially larger than that of irrotational flow. The average energies of collective vibrations, reduced friction, and effective damping coefficients aremore » in better agreement with experimental data than those found from the hydrodynamic model.« less
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