Letter | Published:

Detection of α-Particles in the Disintegration of Thorium

Naturevolume 140page682 (1937) | Download Citation



THE nuclear process (nα), that is, the expulsion of an α-particle by a neutron, has hitherto been observed only for light nuclei ; it probably takes place also in the case of heavy, unstable nuclei. Hahn, Meitner1 and Curie, v. Halban and Preiswerk2 assumed the reaction 23290Th (nα) 22988Ra, and the existence of the radium isotope was established by the latter three by chemical identification.

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  1. 1

    Hahn und Meitner, Naturwiss., 23, 320 (1935).

  2. 2

    Curie, v. Halban and Preiswerk, C.R., 200, 1841 and 2079 (1935); J. Phys., 6, 361 (1935).

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  1. Physikalisches Institut, Eidgenössische Technische Hochschule, Zürich

    • A. BRAUN
    • , P. PREISWERK
    •  & P. SCHERRER


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