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Computational Study of Scission Neutrons in Low-Energy Fission: Stationary and Time-Dependent Approaches

Published online by Cambridge University Press:  20 August 2015

M. Rizea  and
N. Carjan
M. Rizea*
Affiliation:
National Institute of Physics and Nuclear Engineering, “Horia Hulubei”, PO Box MG-6, Bucharest, Romania
N. Carjan*
Affiliation:
National Institute of Physics and Nuclear Engineering, “Horia Hulubei”, PO Box MG-6, Bucharest, Romania Centre d’Etudes Nucléaires de Bordeaux-Gradignan, UMR 5797, CNRS/IN2P3-Université Bordeaux 1, BP 120, 33175 Gradignan Cedex, France
*
Corresponding author.Email:rizea@theory.nipne.ro
Email:carjan@cenbg.in2p3.fr
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Abstract

The emission of scission neutrons from fissioning nuclei is of high practical interest. To study this process we have used the sudden approximation and also a more realistic approach that takes into account the scission dynamics. Numerically, this implies the solution of the bi-dimensional Schrödinger equation, both stationary and time-dependent. To describe axially symmetric extremely deformed nuclear shapes, we have used the Cassini parametrization. The Hamiltonian is discretized by using finite difference approximations of the derivatives. The main computational challenges are the solution of algebraic eigenvalue problems and of linear systems with large sparse matrices. We have employed appropriate procedures (Arnoldi and bi-conjugate gradients). The numerical solutions have been used to evaluate physical quantities, like the number of emitted neutrons per scission event, the primary fragments’ excitation energy and the distribution of the emission points.

Keywords

65M0681Q0502.60.Lj02.70.Bf25.85.EcScission neutronsfissionbi-dimensional Schrödinger equationstationarytime-dependentnon-standard finite differences
Type
Research Article
Information
Communications in Computational Physics , Volume 9 , Issue 4 , April 2011 , pp. 917 - 936
Copyright
Copyright © Global Science Press Limited 2011

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