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Title: Consistent analysis of fusion data without adjustable parameters for a wide variety of heavy-ion systems

Abstract

We have calculated fusion cross sections for 64 heavy-ion systems based on a method that takes into account the couplings to a complete set of states for surface vibrations of the nuclear densities. For the nuclear interaction we have assumed the parameter-free Sao Paulo potential. The predictions have been obtained without using any adjustable parameter, and are in good agreement with the experimental results for most of the systems, even at sub-barrier energies.

Authors:
; ; ; ;  [1];  [2];  [3];  [4]
  1. Departamento de Fisica Nuclear, Instituto de Fisica da Universidade de Sao Paulo, Caixa Postal 66318, 05315-970, Sao Paulo, SP (Brazil)
  2. (Australia)
  3. (Brazil)
  4. (United Kingdom)
Publication Date:
OSTI Identifier:
20995215
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevC.75.044606; (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; COUPLINGS; CROSS SECTIONS; HEAVY ION FUSION REACTIONS; HEAVY IONS; NUCLEAR MATTER; POTENTIALS; SURFACES

Citation Formats

Nobre, G. P. A., Chamon, L. C., Gasques, L. R., Carlson, B. V., Thompson, I. J., Department of Nuclear Physics, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200, Departamento de Fisica, Instituto Tecnologico de Aeronautica, Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP, and University of Surrey, Guildford, Surrey GU2 7XH. Consistent analysis of fusion data without adjustable parameters for a wide variety of heavy-ion systems. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.044606.
Nobre, G. P. A., Chamon, L. C., Gasques, L. R., Carlson, B. V., Thompson, I. J., Department of Nuclear Physics, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200, Departamento de Fisica, Instituto Tecnologico de Aeronautica, Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP, & University of Surrey, Guildford, Surrey GU2 7XH. Consistent analysis of fusion data without adjustable parameters for a wide variety of heavy-ion systems. United States. doi:10.1103/PHYSREVC.75.044606.
Nobre, G. P. A., Chamon, L. C., Gasques, L. R., Carlson, B. V., Thompson, I. J., Department of Nuclear Physics, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200, Departamento de Fisica, Instituto Tecnologico de Aeronautica, Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP, and University of Surrey, Guildford, Surrey GU2 7XH. Sun . "Consistent analysis of fusion data without adjustable parameters for a wide variety of heavy-ion systems". United States. doi:10.1103/PHYSREVC.75.044606.
@article{osti_20995215,
title = {Consistent analysis of fusion data without adjustable parameters for a wide variety of heavy-ion systems},
author = {Nobre, G. P. A. and Chamon, L. C. and Gasques, L. R. and Carlson, B. V. and Thompson, I. J. and Department of Nuclear Physics, Research School of Physical Sciences and Engineering, Australian National University, Canberra ACT 0200 and Departamento de Fisica, Instituto Tecnologico de Aeronautica, Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP and University of Surrey, Guildford, Surrey GU2 7XH},
abstractNote = {We have calculated fusion cross sections for 64 heavy-ion systems based on a method that takes into account the couplings to a complete set of states for surface vibrations of the nuclear densities. For the nuclear interaction we have assumed the parameter-free Sao Paulo potential. The predictions have been obtained without using any adjustable parameter, and are in good agreement with the experimental results for most of the systems, even at sub-barrier energies.},
doi = {10.1103/PHYSREVC.75.044606},
journal = {Physical Review. C, Nuclear Physics},
number = 4,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
  • In a recent article, we calculated fusion cross sections for systems involving even-even nuclei based on a method that takes into account the couplings to a complete set of states for surface vibrations of the nuclear densities. The predictions were obtained without using any adjustable parameter, and are in good agreement with the experimental results for most of the systems, even at sub-barrier energies. In the present work, we extend these calculations to systems involving nuclei with odd number of protons and/or of neutrons.
  • Fusion cross-section data are presented as a function of center-of-mass energy for different reactions involving light and medium-light heavy-ion systems with compound atomic mass number between 18 and 80. The systems range from /sup 6/Li+/sup 12/C to /sup 40/Ca+/sup 40/Ca. The data are given for the region starting from slightly below the Coulomb barrier energy to about six to seven times its value, if they are available. This compilation is primarily to facilitate theoretical interpretation of experimental results. It also serves to give researchers an overview of the range and status of the data. Literature published to June 1983 hasmore » been surveyed.« less
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  • Atomic-resolution imaging in the scanning transmission electron microscope (STEM) constitutes a powerful tool for nanostructure characterization. Here, we demonstrate the quantitative interpretation of atomic-resolution high-angle annular dark-field (ADF) STEM images using an approach that does not rely on adjustable parameters. We measure independently the instrumental parameters that affect sub-0.1 nm-resolution ADF images, quantify their individual and collective contributions to the image intensity, and show that knowledge of these parameters enables a quantitative interpretation of the absolute intensity and contrast across all accessible spatial frequencies. The analysis also provides a method for the in-situ measurement of the STEM's effective source distribution.
  • Graphite and platinum sensors were investigated as indicators in the potentiometric titration of fluoride vs lanthanum(III) and thorium(IV). In every case a partially nonaqueous medium (60% methanol) yielded larger breaks than in aqueous solution, similar to the fluoride electrode. All the sensors yielded endpoint breaks which were smaller than those obtained with the vitreous carbon, pyrolytic graphite, and platinum sensors. Conditioning in neutral permanganate solution significantly enhanced the breaks for all types of graphite, except vitreous carbon. The break obtained with the platinum electrode can be enhanced by application of a polarizing current of 2.0 ..mu..A in the reducing direction.more » 18 references, 2 figures, 6 tables.« less