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Zeitschrift für Physik A Atoms and Nuclei

, Volume 316, Issue 3, pp 291–307 | Cite as

Probing sub-barrier fusion and extra-push by measuring fermium evaporation residues in different heavy ion reactions

  • H. Gäggeler
  • T. Sikkeland
  • G. Wirth
  • W. Brüchle
  • W. Bögl
  • G. Franz
  • G. Herrmann
  • J. V. Kratz
  • M. Schädel
  • K. Sümmerer
  • W. Weber
Nuclei

Abstract

The production of fermium isotopes was attempted by complete fusion of different targets and projectiles spanning a wide range of effective entrance channel fissilities below and above the predicted threshold valuex eff thr ≃0.7. For the most asymmetric systems where fusion is expected to occur without dynamical hindrance we investigate to what extent the expected amount of sub-barrier fusion contributes to the production of fermium evaporation residues. For increasingly symmetric systems the experimental fusion barriers are found to exceed the fusion barriers predicted by the proximity formalism. The barrier heights are discussed in the framework of both the extra-push model and the surface friction model.

Keywords

Evaporation Elementary Particle Barrier Height Surface Friction Friction Model 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1984

Authors and Affiliations

  • H. Gäggeler
    • 1
  • T. Sikkeland
    • 1
  • G. Wirth
    • 1
  • W. Brüchle
    • 1
  • W. Bögl
    • 1
  • G. Franz
    • 1
  • G. Herrmann
    • 1
    • 2
  • J. V. Kratz
    • 1
  • M. Schädel
    • 1
  • K. Sümmerer
    • 1
  • W. Weber
    • 1
  1. 1.Gesellschaft für Schwerionenforschung mbHDarmstadtFederal Republic of Germany
  2. 2.Institut für KernchemieUniversität MainzFRG

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