Perturbative QCD. II. OZI Decays; Drell—Yan Processes; Jets; Corrections to Weak Decays; SVZ Sum Rules; Exclusive Processes

  • F. J. Ynduráin
Part of the Texts and Monographs in Physics book series (TMP)


The Zweig (1964) or 0ZI1 rule states that decays of heavy resonances which involve disconnected quark graphs (i.e., graphs that can be connected only via gluons) are suppressed. The rule works well for resonances like the ø or f’ and very well for the ψ or γ: in fact, the heavier the quarks and the resonance, the better the rule works. Consider, for example, the ψ particles made up of \( \bar cc \) quarks.


Transverse Momentum Heavy Quark Deep Inelastic Scattering Vertex Correction Pion Form Factor 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • F. J. Ynduráin
    • 1
  1. 1.Departamento de Física Teórica, C-XIUniversidad Autónoma de Madrid, Canto BlancoMadridSpain

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