Il Nuovo Cimento (1955-1965)

, Volume 24, Issue 3, pp 497–507 | Cite as

The unitary simmetry and a connection between the ¦δs¦≠1/2 and ¦δi¦ = 2 rules

  • B. d’Espagnat
  • J. Prentki


The assumption is made that the weak interactions are invariant under a three-dimensional rotation subgroup «G » ofSU3, which of course is not the isospin subgroup. It is then shown that for non-leptonic and leptonic decays, the rule ¦ΔI¦ = 1/2 follows from the requirement ¦ΔS¦≠ 2 and vice-versa. In such a theory these selection rules are equivalent.


Si fa l’ipotesi che le interazioni deboli siano invarianti per un sottogruppo tridimensionale di rotazione «G » diSU2, che non è, naturalmente, il sottogruppo dell’isospin. Si dimostra poi che per decadimenti leptonici e non leptonici, la legge ¦ΔI¦=1/2 dériva dalla condizione ¦ΔS¦ ≠ 2 e viceversa. In tale teoria queste leggi di selezione sono equivalenti.


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Copyright information

© Società Italiana di Fisica 1962

Authors and Affiliations

  • B. d’Espagnat
    • 1
  • J. Prentki
    • 1
  1. 1.CERNGeneva

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