Number of Neutrons Liberated in the Nuclear Fission of Uranium

  title={Number of Neutrons Liberated in the Nuclear Fission of Uranium},
  author={HANS H. v. Halban and Fr{\'e}d{\'e}ric Joliot and Lew 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. 

Energy Release in Nuclear Reactions, Neutrons, Fission, and Characteristics of Fission

  • B. Reed
  • Physics
    The Physics of the Manhattan Project
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This introductory chapter covers the background nuclear physics necessary for understanding later calculations of critical mass, nuclear weapon efficiency and yield, and how fissile materials are

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Review of the Measurements of the Resonance Absorption of Neutrons by Uranium in Bulk

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THE first indication that the transmutation of heavy nuclei could be effected in a laboratory experiment was obtained by Fermi in March 1934. Curie and Joliot had just discovered that shortlived

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  • B. Reed
  • Physics
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  • 2019
If the story of the four-year progression from Enrico Fermi’s discovery of neutron-induced radioactivity to the discovery of fission were cast as a suspense novel, it would probably be considered too

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The following article presents preliminary estimates of the economic importance of nuclear energy and is part of a study being conducted by the Cowles Commission* at the University of Chicago under



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RECENT experiments1,2 have revealed the existence of a new kind of nuclear reaction: neutron bombardment of uranium and thorium loads to an explosion of the nucleus, which splits up into particles of

Über die Umwandlungsreihen des Urans, die durch Neutronenbestrahlung erzeugt werden

ZusammenfassungIn einer Reihe vorangehender Arbeiten ist gezeigt worden, daß die Bestrahlung von Uran mit Neutronen zu drei neuen Umwandlungsreihen führt, deren einzelne Glieder zum größten Teile