Summary
We discuss the value, in the light of recent «two-neutrino» experiments (1), of giving meaning to the neutrino charge or lepton number independent of helicity;i.e., of giving up the two-component neutrino theory and reverting to a single four-component neutrino whose left- and right-helicity states are coupled to e− and μ+, respectively. It is shown that, in fact,only by such experiments, involving muonsand electrons or their neutrinos, can a nontrivial meaning be given to lepton conservation. This Dirac neutrino theory is compared with the conventional theory of two two-component neutrinos from the conceptual and experimental points of view. Some remarks are made about the possibility of explaining the μ—e mass difference.
Riassunto
Alla luce dei recenti esperimenti sui due neutrini (1), si discute l’opportunità, di dar significato alla carica od al numero leptonico del neutrino indipendentemente dall’elicità; cioè, di abbandonare la teoria del neutrino a due componenti e di tornare al neutrino singolo con quattro componenti i cui stati con elicità sinistra e destra sono accoppiati rispettivamente all’e− ed al μ+. Si dimostra che, in effetti, solo conquesti esperimenti, che coinvolgono muonied elettroni od i loro neutrini, si può attribuire un significato non banale alla conservazione leptonica. Si paragona questa teoria del neutrino di Dirac con la teoria convenzionale dei due neutrini con due componenti dai punti di vista concettuale e sperimentale. Si fanno alcune osservazioni sulla possibilità di spiegare la differenza di massa μ—e.
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This work was supported by the U. S. Atomic Energy Commission.
This paper was written while the author was a guest of the Lawrence Radiation Laboratory, Berkeley, Calif., whose hospitality he gratefully acknowledges.
Traduzione a cura della Redazione.
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Bludman, S.A. Two neutrinos or one?. Nuovo Cim 27, 751–760 (1963). https://doi.org/10.1007/BF02784579
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DOI: https://doi.org/10.1007/BF02784579