Allowance for the tunnel effect in the entrance channel of fusion–fission reactions

doi:10.1134/S1063778816020113

Title: Allowance for the tunnel effect in the entrance channel of fusion–fission reactions

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Abstract

A two-stage model is developed in order to describe fusion–fission reactions. The process in the course of which colliding ions approach each other is simulated at the first stage, the deformations and relative orientations of the ions being taken into account. The first stage of the calculation is completed as soon as colliding nuclei touch each other. A continuous nuclear system (monosystem) is formed at this instant. The emerging distributions of the angular momenta of this system and of its potential and internal energies at the point of touching are used as input data that are necessary for triggering the second stage of the calculation. The evolution of collective coordinates that describe the shape of the monosystem is calculated at the second stage. The description of this evolution is terminated either at the instant of its fission or upon the release of a major part of its excess energy via particle and photon emission. In the latter case, the probability for the fission of the monosystem or a further decrease in its excitation energy becomes extremely small. The ion-collision process and the evolution of the monosystem formed after primary nuclei come into contact are simulated on the basis of stochasticmore »« less

Authors:

Litnevsky, V. L., E-mail: vlad.lit@bk.ru; Kosenko, G. I., E-mail: kosenkophys@gmail.com ^[1]; Ivanyuk, F. A., E-mail: ivanyuk@kinr.kiev.ua ^[2]

Omsk Tank-Automative Engineering Institute (Russian Federation)
National Academy of Sciences of Ukraine, Institute for Nuclear Research (Ukraine)

Publication Date:: Sun May 15 00:00:00 EDT 2016

OSTI Identifier:: 22612668

Resource Type:: Journal Article

Journal Name:: Physics of Atomic Nuclei

Additional Journal Information:: Journal Volume: 79; Journal Issue: 3; Other Information: Copyright (c) 2016 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1063-7788

Country of Publication:: United States

Language:: English

Subject:: 74 ATOMIC AND MOLECULAR PHYSICS; ANGULAR MOMENTUM; COMPUTERIZED SIMULATION; COORDINATES; COULOMB FIELD; DEFORMATION; EXCITATION; FISSION; HEAVY ION FUSION REACTIONS; ION COLLISIONS; IONS; LANGEVIN EQUATION; NUCLEI; ORIENTATION; PHOTON EMISSION; PHOTONS; POTENTIAL ENERGY; PROBABILITY; STOCHASTIC PROCESSES; TUNNEL EFFECT

Citation Formats


                    Litnevsky, V. L., E-mail: vlad.lit@bk.ru, Kosenko, G. I., E-mail: kosenkophys@gmail.com, and Ivanyuk, F. A., E-mail: ivanyuk@kinr.kiev.ua. Allowance for the tunnel effect in the entrance channel of fusion–fission reactions.  United States: N. p., 2016. 
        Web.  doi:10.1134/S1063778816020113.

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                    Litnevsky, V. L., E-mail: vlad.lit@bk.ru, Kosenko, G. I., E-mail: kosenkophys@gmail.com, & Ivanyuk, F. A., E-mail: ivanyuk@kinr.kiev.ua. Allowance for the tunnel effect in the entrance channel of fusion–fission reactions.  United States.  https://doi.org/10.1134/S1063778816020113

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                    Litnevsky, V. L., E-mail: vlad.lit@bk.ru, Kosenko, G. I., E-mail: kosenkophys@gmail.com, and Ivanyuk, F. A., E-mail: ivanyuk@kinr.kiev.ua. 2016.  
        "Allowance for the tunnel effect in the entrance channel of fusion–fission reactions".  United States.  https://doi.org/10.1134/S1063778816020113.

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@article{osti_22612668,

  title        = {Allowance for the tunnel effect in the entrance channel of fusion–fission reactions},

  author       = {Litnevsky, V. L., E-mail: vlad.lit@bk.ru and Kosenko, G. I., E-mail: kosenkophys@gmail.com and Ivanyuk, F. A., E-mail: ivanyuk@kinr.kiev.ua},

  abstractNote = {A two-stage model is developed in order to describe fusion–fission reactions. The process in the course of which colliding ions approach each other is simulated at the first stage, the deformations and relative orientations of the ions being taken into account. The first stage of the calculation is completed as soon as colliding nuclei touch each other. A continuous nuclear system (monosystem) is formed at this instant. The emerging distributions of the angular momenta of this system and of its potential and internal energies at the point of touching are used as input data that are necessary for triggering the second stage of the calculation. The evolution of collective coordinates that describe the shape of the monosystem is calculated at the second stage. The description of this evolution is terminated either at the instant of its fission or upon the release of a major part of its excess energy via particle and photon emission. In the latter case, the probability for the fission of the monosystem or a further decrease in its excitation energy becomes extremely small. The ion-collision process and the evolution of the monosystem formed after primary nuclei come into contact are simulated on the basis of stochastic Langevin equations. The quantities appearing in them (which include the potential energy and inertial and friction parameters) are determined with allowance for the shell structure of nuclei. The tunneling of colliding nuclei through the Coulomb barrier is taken into account, and the effect of this phenomenon on model predictions is studied.},

  doi          = {10.1134/S1063778816020113},

  url          = {https://www.osti.gov/biblio/22612668},
  journal      = {Physics of Atomic Nuclei},

  issn         = {1063-7788},

  number       = 3,

  volume       = 79,

  place        = {United States},

  year         = {Sun May 15 00:00:00 EDT 2016},

  month        = {Sun May 15 00:00:00 EDT 2016}

}

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