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Universal theory of semi-weak interactions

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Il Nuovo Cimento (1955-1965)

Summary

A universal theory of semi-weak interactions is proposed on the basis of a new baryon-lepton symmetry principle and the conservation of a new quantum numberX, the « weak hypercharge ». The universality of the theory is achieved by coupling two intermediate charged vector bosons of different mass andX assignment to the strangeness-conserving and strangeness-changing currents. Acceptance of the conserved vector current hypothesis for strangeness-conserving processes leads to definite statements concerning the fields describing the electron and muon neutrinos, the (ΔQ/ΔS) properties of the strangeness-changing current and the existence of neutrino flip. The more striking experimental predictions of the theory (e.g., neutrino flip accompanied by hyperon production) are discussed in some detail. Alternative formulations of the theory are examined and it is shown that very little flexibility is allowed within the framework of a dynamical baryon-lepton symmetry principle.

Riassunto

Sulla base di un nuovo principio di simmetria barione-leptone e della conservazione di un nuovo numero quanticoX, la « ipercarica debole », si propone una teoria universale delle interazioni semideboli. Si ottiene l’universalità della teoria accoppiando due bosoni vettoriali carichi intermedi, aventi una massa ed unX differente, alle correnti che conservano o cambiano la stranezza. L’accettazione dell’ipotesi della conservazione della corrente vettoriale nei processi che conservano la stranezza porta a definire affermazioni sui campi che descrivono i neutrini dell’elettrone e del muone, sulle proprietà (ΔQ/ΔS) della corrente che cambia la stranezza e sull’esistenza del flip neutrinico. Si discutono dettagliatamente le più notevoli predizioni della teoria (per es. il flip neutrinico accompagnato da produzione di iperoni). Si esaminano delle altre formulazioni della teoria e si dimostra che la struttura del principio dinamico di simmetria barione-leptone consente una flessibilità minima.

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References

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Author notes

  1. C. Ryan

    Present address: the Institute for Advanced Studies, Dublin

  2. T. K. Radha

    Present address: Institute for Mathematical Sciences, Madras

Authors and Affiliations

  1. University of Rochester, Rochester, N. Y.

    R. E. Marshak & C. Ryan

  2. Institute for Theoretical Physics, Department of Physics, Stanford University, Stanford, Cal.

    T. K. Radha

  3. Institute for Mathematical Sciences, Madras

    K. Raman (Research Follow)

  4. the Deparment of Atomic Energy, Government of India, India

    K. Raman (Research Follow)

Authors
  1. R. E. Marshak
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  2. C. Ryan
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  3. T. K. Radha
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  4. K. Raman
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Additional information

This work was supported in part by the U. S. Atomic Energy Commission an by the U.S. Air Force Office of Scientific Research under Grant AF-AFOSR-62-452.

This work was started in February 1963 while one of the authors (R.E.M.) was Niels Bohr Visiting Professor at the Institute for Mathematical Sciences, Madras, India.

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Marshak, R.E., Ryan, C., Radha, T.K. et al. Universal theory of semi-weak interactions. Nuovo Cim 32, 408–432 (1964). https://doi.org/10.1007/BF02733970

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