Low and High Resolution Protonium Spectroscopy at LEAR in Acol Time: Tools for Glueball, Hybrid and Light Meson Spectroscopy and for Measuring the NN̄ Strong Interaction Dependence on Angular Momentum

  • Ugo Gastaldi
Part of the Ettore Majorana International Science Series book series (EMISS, volume 31)


The p̄p atom is a simple system that permits to study NN̄ strong interactions at threshold in depth and to exploit NN̄ annihilations for light and exotic mesons spectroscopy. The study of NN̄ interactions in depth at threshold requires to measure individually all the annihilation channels, to measure the global effects of all open annihilation channels (that reflect in the hadronic width of protonium atomic levels) and to measure the global effects of virtual elastic and charge exchange and of all open virtual annihilation channels (that reflect in the hadronic shift of the atomic levels). Ideally these studies should be done for all JPC states of protonium with L=0 and 1 in order to get the complete picture of the dynamics of the strong interaction and of its dependence on the quantum numbers of the initial state. The search of new mesonic resonances in pp annihilation requires to measure exclusive annihilation channels and the intermediate resonant states. This search and the study of the dynamics of NN annihilations at threshold are one a byproduct of the other. Experimentally two lines of research are open with different requirements from the X-ray detectors used for protonium spectroscopy.


Straight Section Electron Cool Annihilation Channel Protonium Spectroscopy Strong Interaction Effect 
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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Ugo Gastaldi
    • 1
  1. 1.CERNGeneva 23Switzerland

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