Dynamical description of the moments of the energy distribution of fission fragments and scission of a fissile nucleus
Abstract
A multidimensional stochastic approach to fission dynamics on the basis of threedimensional Langevin equations is applied systematically to calculating the first four moments of the energy distribution of fission fragments over a broad range of Coulomb parameter values (700 < Z{sup 2}/A{sup 1/3} < 1700). For the scission of a fissile nucleus into fragments, use was made of various criteria traditional in modern fission theory: the vanishing of the neck radius at the scission instant and the equality of the neck radius to about 0.3R{sub 0} at this instant. In calculating the energy distribution, both of the criteria used lead to a fairly good description of experimental data on the first two moments and to a satisfactory description of data on the third and fourth moments of the distribution. However, the quality of the description of available experimental data is insufficiently good for giving preference to any of these criteria. Within threedimensional Langevin dynamics, it is shown that the vanishingradius criterion leads to unexpectably good agreement with experimental data on the first four moments of the energy distribution. A modified version of onebody dissipation where the coefficient that takes into account the reduction of the wallformula contribution was set tomore »
 Authors:
 Omsk State University (Russian Federation)
 Publication Date:
 OSTI Identifier:
 21399926
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Atomic Nuclei; Journal Volume: 70; Journal Issue: 11; Other Information: DOI: 10.1134/S106377880711004X; Copyright (c) 2007 Pleiades Publishing, Ltd.
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ENERGY SPECTRA; EXPERIMENTAL DATA; FISSILE MATERIALS; FISSION; FISSION FRAGMENTS; LANGEVIN EQUATION; STOCHASTIC PROCESSES; THREEDIMENSIONAL CALCULATIONS; DATA; EQUATIONS; FISSIONABLE MATERIALS; INFORMATION; MATERIALS; NUCLEAR FRAGMENTS; NUCLEAR REACTIONS; NUMERICAL DATA; SPECTRA
Citation Formats
Borunov, M. V., Email: bmv@opsb.ru, Nadtochy, P. N., and Adeev, G. D.. Dynamical description of the moments of the energy distribution of fission fragments and scission of a fissile nucleus. United States: N. p., 2007.
Web. doi:10.1134/S106377880711004X.
Borunov, M. V., Email: bmv@opsb.ru, Nadtochy, P. N., & Adeev, G. D.. Dynamical description of the moments of the energy distribution of fission fragments and scission of a fissile nucleus. United States. doi:10.1134/S106377880711004X.
Borunov, M. V., Email: bmv@opsb.ru, Nadtochy, P. N., and Adeev, G. D.. 2007.
"Dynamical description of the moments of the energy distribution of fission fragments and scission of a fissile nucleus". United States.
doi:10.1134/S106377880711004X.
@article{osti_21399926,
title = {Dynamical description of the moments of the energy distribution of fission fragments and scission of a fissile nucleus},
author = {Borunov, M. V., Email: bmv@opsb.ru and Nadtochy, P. N. and Adeev, G. D.},
abstractNote = {A multidimensional stochastic approach to fission dynamics on the basis of threedimensional Langevin equations is applied systematically to calculating the first four moments of the energy distribution of fission fragments over a broad range of Coulomb parameter values (700 < Z{sup 2}/A{sup 1/3} < 1700). For the scission of a fissile nucleus into fragments, use was made of various criteria traditional in modern fission theory: the vanishing of the neck radius at the scission instant and the equality of the neck radius to about 0.3R{sub 0} at this instant. In calculating the energy distribution, both of the criteria used lead to a fairly good description of experimental data on the first two moments and to a satisfactory description of data on the third and fourth moments of the distribution. However, the quality of the description of available experimental data is insufficiently good for giving preference to any of these criteria. Within threedimensional Langevin dynamics, it is shown that the vanishingradius criterion leads to unexpectably good agreement with experimental data on the first four moments of the energy distribution. A modified version of onebody dissipation where the coefficient that takes into account the reduction of the wallformula contribution was set to k{sub s} = 0.25 was used in the calculations.},
doi = {10.1134/S106377880711004X},
journal = {Physics of Atomic Nuclei},
number = 11,
volume = 70,
place = {United States},
year = 2007,
month =
}

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Dynamical description of the variances of the kinetic energy of fission fragments
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