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Zeitschrift für Physik A Atoms and Nuclei

, Volume 303, Issue 3, pp 173–188 | Cite as

The decay of the vacuum in the field of superheavy nuclear systems

  • J. Reinhardt
  • U. Müller
  • B. Müller
  • W. Greiner
Atoms

Abstract

In the strong Coulomb field of a nucleus or quasimolecule withZ≳172 a change of the QED vacuum has been predicted, signalled by the spontaneous emission of positrons if holes in theK-shell are available. The dynamical semiclassical theory of positron excitation in heavy ion scattering is presented and extended to collisions with nuclear contact. Interference patterns in the energy spectrum of the emitted positrons and, for sufficiently long reaction timeT, the emerging of a characteristic line at the position of the 1-resonance is predicted. The position and width of the 1-resonance is calculated in dependence on the nuclear configuration, the effect of electron screening is taken into account. Recent experimental indications [1, 2] for structures in the spectra of positrons emitted in U-U collisions at energies close to the Coulomb barrier are discussed in terms of spontaneous positron creation. The observed spectra could be explained under the assumption of long lasting nuclear reactions (T≳4·10−20 s) with a cross section in the millibarn region. Various consequences of this interpretation are discussed.

Keywords

Energy Spectrum Nuclear Reaction Interference Pattern Spontaneous Emission Characteristic Line 
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 1981

Authors and Affiliations

  • J. Reinhardt
    • 1
  • U. Müller
    • 1
  • B. Müller
    • 1
  • W. Greiner
    • 1
  1. 1.Institut für Theoretische PhysikJohann Wolfgang Goethe-UniversitätFrankfurt am MainFederal Republic of Germany

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