Number of Neutrons Liberated in the Nuclear Fission of Uranium

  title={Number of Neutrons Liberated in the Nuclear Fission of Uranium},
  author={H. Halban and F. Joliot and L. Kowarski},
RECENT experiments have shown that neutrons are liberated in the nuclear fission of uranium induced by slow neutron bombardment: secondary neutrons have been observed which show spatial1, energetic2 or temporal3 properties different from those which primary neutrons possess or may acquire. Such observations give no information on the mean number of neutrons produced per nucleus split; this number v may be very small (less than 1) and the result of the experiment will still be positive. 
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