Il Nuovo Cimento (1955-1965)

, Volume 27, Issue 2, pp 513–524 | Cite as

Chirality and the structure of the pion-nucleon interaction

  • Y. Oishi


The concept of chirality invariance is extensively applied to the direct four-fermion interaction of the nucleon-antinucleon system. It is shown that if we extend the chirality concept to the isotopic spinor,P-invariance is derived in a natural way, and if we further extend this concept (according to Watanabe-Tanikawa) to the tensor quantities appearing in the interaction Lagrangian, (parity conserving)V+A orV−A is suggested as the type of basic interaction. Based on the Fermi-Yang model, effective pion-nucleon couplings are derived by the use of the chain approximation, and it is found that theV+A andV−A correspond to the pseudoscalar and pseudovector pion-nucleon couplings respectively. Some remarks concerning the results are made, in view of the symmetry of strong interactions.


Si applica estensivamente il concetto di invarianza della chiralità alle interazioni dirette con quattro fermioni del sistema nucleone-antinucleone. Si dimostra che se estendiamo il concetto di chiralità allo spinore isotopico, l’invarianza delP si può dedurre in modo naturale, e l’estensione ulteriore di questo concetto (secondo Watanabe-Tanikawa) alle grandezze tensoriali che compaiono nel lagrangiano di interazione, suggerisceV+A oV−A (con conservazione di parità) come tipo di interazione fondamentale. Sulla base del modello di Fermi-Yang, con l’uso dell’approssimazione a catena, si deducono accoppiamenti pione-nucleone effettivi, e si trova cheV+A eV−A corrispondono rispettivamente agli accoppiamenti pione-nucleone pseudo-scalare e pseudovettoriale. Si fanno alcune osservazioni riguardanti i risultati, in vista della simmetria delle interazioni forti.


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Copyright information

© Società Italiana di Fisica 1963

Authors and Affiliations

  • Y. Oishi
    • 1
  1. 1.Kochi

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