Elsevier

Nuclear Physics A

Volume 289, Issue 1, 10 October 1977, Pages 236-252
Nuclear Physics A

9Be + 12C, 9Be + 16O,9Be + 19F reactions at energies below the barrier

https://doi.org/10.1016/0375-9474(77)90531-0Get rights and content

Abstract

The 16O + 9Be reactions have been studied from Ec.m. = 2.0 MeV to 5.1 MeV, an energy near the top of the Coulomb barrier. The cross section for the neutron transfer reaction 9Be(16O,17O (0.87 MeV))8Be has been measured over this range by detecting the prompt 0.87 MeV γ-rays. The total fusion cross section has been determined from Ec.m. = 2.8 to 5.1 MeV by observing individual γ-ray transitions in the evaporation residues with a Ge(Li) detector, and then summing the separate yields. Direct processes are found to dominate the reaction yield below Ec.m. = 4 MeV. A comparison of the energy dependence of the fusion cross section for this reaction and the 12C + 13C reaction, which proceeds via the formation of the same compound nucleus, 25Mg, reveals differences at sub-barrier energies. Optical model and incoming-wave boundary condition calculations are presented. Data have also been obtained for the near optimum Q-value neutron-transfer reactions 9Be(12C, 13C)8Be and 9Be(19F, 20F)8Be, and these are discussed in terms of a simple model of sub-barrier direct reactions.

References (21)

  • R.A. Dayras et al.

    Nucl. Phys.

    (1976)
  • Z.E. Switkowski et al.

    Nucl. Phys.

    (1976)
  • Z.E. Switkowski et al.

    Nucl. Instr.

    (1975)
    C. A. Barnes, J. C. Overley, Z. E. Switkowski and T. A. Tombrello, Appl. Phys. Lett., in...
  • L.C. Northcliffe et al.

    Nucl. Data Tables

    (1970)
  • B. Čujec et al.

    Nucl. Phys.

    (1976)
  • P.R. Christensen et al.

    Nucl. Phys.

    (1977)
  • R.A. Dayras et al.

    Nucl. Phys.

    (1976)
  • C.A. Barnes
  • G.J. Michaud

    Phys. Rev.

    (1973)
  • P.R. Christensen et al.

    Phys. Lett.

    (1976)
There are more references available in the full text version of this article.

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Supported in part by the National Science Foundation [PHY76-83685].

††

Present address: School Physics, University of Melbourne, Parkville 3052, Australia.

†††

Permanent address: Physics Department, University of Oregon, Eugene, Oregon 97403.

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