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Energy Spectrum of Secondary Electrons from μ-Meson Decay


RECENT experimental results are strongly in favour of the decay of the μ-meson into more than two particles1. The energy spectrum of the electron emitted in the disintegration of the μ-meson at rest has been calculated on the following assumptions. The μ-meson has spin ½; it decays spontaneously according to the scheme μ ± â ϵ ± + Î + ν, where ϵ indicates an electron, ν a neutrino and Î a neutral particle of spin ½ with a mass either non-vanishing (μ0 of Powell2) or more probably zero, in which case it can be identified with a neutrino.

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MICHEL, L. Energy Spectrum of Secondary Electrons from μ-Meson Decay. Nature 163, 959–960 (1949).

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