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Behaviour of a Particle of Very Small Mass in a Magnetic Field

Nature volume 162, page 329 (28 August 1948) | Download Citation



IT would seem at first sight that a particle of very small mass, such as accompanies β-disintegration or electron-capture, and significant magnetic moment μ, would be very difficult to observe. According to Bethe1, it should have a fairly high ionizing power and a correspondingly small penetration into matter. Moreover, if it already possesses a charge e, the uncertainty principle should play a part in all cases where experimental evidence on μ would be sought2. However, for an ultra-relativistic particle (that is, a particle with a high ratio of kinetic mass to rest mass) special considerations come into play which may modify the generally accepted conclusions.

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    , Proc. Camb. Phil. Soc., 31, 115 (1935).

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    , Proc. Roy. Soc., A, 130, 637 (1931). , 1930 (Gauthier-Villars, Paris).

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    , Z. Phys., 37, 4–5, 243.

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    , "L‘Electron Magnetique", 192 (Hermann, 1934).

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    , "L‘Electron Magnetique", 190 (Hermann, 1934).

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    , C.R. Acad. Sci. Paris, 226, 482 (1948).

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  1. Institute of Atomic Physics, University of Lyons, 1 rue Raulin, Lyons. May 8.

    • J. THIBAUD


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