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Title: Semiclassical calculation of heavy-ion scattering in the chaotic regime

Abstract

The semiclassical approach has proven to be a most valuable tool for the construction of the scattering matrix and accurate evaluation of cross sections in a large variety of heavy-ion collision problems. In its familiar implementation, however, its use is restricted to what is now known as the 'regular regime', as it makes use of classical reaction functions that must be continuous and interpolable. In this paper we identify what version of the semiclassical formalisms may be especially suitable for extension into the chaotic regime that develops at energies close to the Coulomb barrier. We also show the crucial role of the absorptive part of the ion-ion potential to retain the usefulness of the semiclassical methods under conditions of irregularity.

Authors:
;  [1];  [2];  [3]
  1. Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, Apdo. 1065, E-41080 Sevilla (Spain)
  2. Departamento de Fisica, Comision Nacional de Energia Atomica, Av. del Libertador 8250, Buenos Aires (Argentina)
  3. (B1653HIM), Villa Ballester (Argentina)
Publication Date:
OSTI Identifier:
20995297
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.75.054611; (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; CHAOS THEORY; COULOMB FIELD; HEAVY ION REACTIONS; HEAVY IONS; ION-ION COLLISIONS; SCATTERING; SEMICLASSICAL APPROXIMATION

Citation Formats

Dasso, C. H., Gallardo, M. I., Saraceno, M., and Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin, Alem 3901. Semiclassical calculation of heavy-ion scattering in the chaotic regime. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.054611.
Dasso, C. H., Gallardo, M. I., Saraceno, M., & Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin, Alem 3901. Semiclassical calculation of heavy-ion scattering in the chaotic regime. United States. doi:10.1103/PHYSREVC.75.054611.
Dasso, C. H., Gallardo, M. I., Saraceno, M., and Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin, Alem 3901. Tue . "Semiclassical calculation of heavy-ion scattering in the chaotic regime". United States. doi:10.1103/PHYSREVC.75.054611.
@article{osti_20995297,
title = {Semiclassical calculation of heavy-ion scattering in the chaotic regime},
author = {Dasso, C. H. and Gallardo, M. I. and Saraceno, M. and Escuela de Ciencia y Tecnologia, Universidad Nacional de San Martin, Alem 3901},
abstractNote = {The semiclassical approach has proven to be a most valuable tool for the construction of the scattering matrix and accurate evaluation of cross sections in a large variety of heavy-ion collision problems. In its familiar implementation, however, its use is restricted to what is now known as the 'regular regime', as it makes use of classical reaction functions that must be continuous and interpolable. In this paper we identify what version of the semiclassical formalisms may be especially suitable for extension into the chaotic regime that develops at energies close to the Coulomb barrier. We also show the crucial role of the absorptive part of the ion-ion potential to retain the usefulness of the semiclassical methods under conditions of irregularity.},
doi = {10.1103/PHYSREVC.75.054611},
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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  • A generalized semiclassical treatment for the elastic scattering of heavy ions is developed in the presence of a complex optical potential. The scattering phase shift and its derivatives with respect to the impact parameter are calculated after extending the JWKBL approximation. The results are compared with experimental data for the elastic scattering of 160 from medium and heavy target nuclei and, a relation between the present treatment and that of the optical model and Regge pole analysis is established. (orig.) (GE)
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