Letter | Published:

Relationships between the Masses of Subatomic Particles

Nature volume 216, pages 784786 (25 November 1967) | Download Citation



IN a previous communication1, the bound rest mass of the proposed tamaid particle, t0, was calculated from available experimental data2 to be equivalent to 25.95 MeV. The subatomic particles of zero charge have been shown to fall into a quantized series obeying the relationship Mass of subatomic particle = M = 25.95 n + 134.97 (1) Here n is an integral quantum number and the constant term is the mass of the π0 meson. From a consideration of the available numerical data the possible existence is now postulated of another mass—energy entity, b, which, in association with the tamaid, could be employed to build up units of matter which correspond to all the known muons, mesons, baryons, etc. It is proposed to call this subsidiary entity a “bach” (Welsh—the little one), and present calculations suggest that it has a bound rest mass corresponding to b = 0.3263 MeV. It is therefore smaller than the electron (e = 0.511 MeV) and must be associated with a larger De Broglie wavelength.

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  1. 1.

    , Nature, 216, 573 (1967).

  2. 2.

    , Atom. Ener. Rev., 5, 47 (1967).

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  1. Laboratory of the Government Chemist, Stamford Street, London.

    • D. T. LEWIS


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