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Positron Line Emission in Very Heavy Ion Collisions: Results from the EPOS Collaboration

  • H. Bokemeyer
Part of the NATO ASI Series book series (NSSB, volume 255)

Abstract

The detection of narrow lines in positron singles- and electron positron sum-energy spectra measured after heavy-ion collisions at the UNILAC accelerator of GSI, Darmstadt has generated increasing interest in the past years. Whereas the line phenomenon itself appears to be experimentally well established, no conceivable explanation is given until today although many different attempts have been made. They reach from conventional processes to newly proposed mechanisms, including spontaneous positron emission in long-living quasiatomic heavy-ion formations as well as the production of light neutral fundamental particles. This article summarizes some of the main features of the positron lines as they have been obtained by the EPOS collaboration [SalB90]. No attempt is made to describe the experiment itself in full detail; instead we refer to [BokS89,Bok87,CowG87,Bok90]. Two other groups, the ORANGE [KoeB87,KoeB89] and the TORI [RheB89] collaborations are also studying these subjects. For the results of the ORANGE group see the contribution of W. Koenig to this conference. Comprehensive collections of theoretical aspects have been given by various other lectures during this school and can be found e.g. in [Gre88,FacT89] and in a recent review [Mül89].

Keywords

Monte Carlo Collision System Lepton Energy Pair Emission Positron Production 
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

© Plenum Press, New York 1991

Authors and Affiliations

  • H. Bokemeyer
    • 1
  1. 1.Gesellschaft für SchwerionenforschungDarmstadtFed. Rep. of Germany

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