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Studies of4He emission in both fusion-like and inelastic reactions of 340-MeV40Ar+238U

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Zeitschrift für Physik A Atoms and Nuclei

Abstract

The fission-fragment angular correlation technique has been used in conjunction with a position-sensitive avalanche detector to identify the fusion-like and inelastic collisions of 340-MeV40Ar+238U. For each of these two reaction types, we have characterized the correlated4He emission by measuring three-fold coincidences between two fission fragments and the light charged particle. We find an abundance of both evaporation-like and direct4He emission, each of which is associated with both fusion-fission and sequential-fission processes. Several comparison tests of both the coincidence and singles data strongly indicate that very little4He emission is due to evaporation from accelerated fission fragments in this system. The evaporative4He emission appears instead to have a strong contribution originating from the composite system prior to fission. The forward angle4He emissions, characterized by prominent forward-peaking and relatively high energies, suggest an origin associated with the very early stages of the collision.

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Author notes

  1. M. Kildir

    Present address: Department of Chemistry, Middle East Technical University, Ankara, Turkey

  2. D. Guerreau

    Present address: Laboratoire de Chimie Nucléaire, Institut de Physique Nucléaire, B.P. No. 1, F-91406, Orsay, France

Authors and Affiliations

  1. Department of Chemistry, Carnegie-Mellon University, Pittsburgh, Pennsylvania, USA

    M. Kildir, D. Logan & Morton Kaplan

  2. Lawrence Berkeley Laboratory, Berkeley, California, USA

    M. S. Zisman

  3. Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York, USA

    D. Guerreau, John M. Alexander & L. C. Vaz

Authors
  1. M. Kildir
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  2. D. Logan
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  3. Morton Kaplan
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  4. M. S. Zisman
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  5. D. Guerreau
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  6. John M. Alexander
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  7. L. C. Vaz
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Additional information

We appreciate the cooperation and effort extended by the SuperHILAC staff in the performance of this experiment. The helpful discussions and assistance of our colleagues E. Duek, D. Eriksen, D. Moses, and A. Frisch are acknowledged. This work has been supported by the Division of Nuclear Physics, Office of High Energy and Nuclear Physics, U.S. Department of Energy.

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Kildir, M., Logan, D., Kaplan, M. et al. Studies of4He emission in both fusion-like and inelastic reactions of 340-MeV40Ar+238U. Z Physik A 306, 323–334 (1982). https://doi.org/10.1007/BF01432373

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  • DOI: https://doi.org/10.1007/BF01432373

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