Experiments on Low Energy Bhabha Scattering Search for Neutral Resonances in the MeV/c2 Mass Region

  • C. Kozhuharov
Conference paper


In the last years, a series of experiments on low-energy Bhabha scattering was prompted by the evidence for correlated back-to-back e+e- emission, found in heavy-ion experiments [1–3]. As summarized in the previous contribution [4], several monoenergetic e+e- pairs, with sharp sum energies between 500 keV and 815 keV, were observed. Also reported was the detection of correlated back-to-back emission of two γ-quanta with a sum energy of 1062 keV [5]. One is led to conclude that one deals with the decay of various excited states of a composite extended object with internal structure into e+e- or γγ-pairs. Bearing this in mind, numerous experimental groups addressed themselves to the question of whether such a hypothetical e+e- object could be created in e+e- collisions and whether it would manifest its eventual decay as a resonance in the excitation function for Bhabha scattering (or, in the excitation function for anihilation-in-flight) [6–22]. For the sake of clarity, the list of references is restricted to experimental works only, already published or submitted for publication.


Excitation Function Mass Region Resonance Parameter Partial Decay Width Smooth Distribution 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1989

Authors and Affiliations

  • C. Kozhuharov
    • 1
  1. 1.GSI, Gesellschaft für SchwerionenforschungDarmstadtW. Germany

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