Elsevier

Nuclear Physics A

Volume 361, Issue 1, 18 May 1981, Pages 213-241
Nuclear Physics A

Charge distributions in low-energy nuclear fission and their relevance to fission dynamics

https://doi.org/10.1016/0375-9474(81)90477-2Get rights and content

Abstract

Radiochemical and energy loss techniques have been used to measure fragment charge distributions in the systems 229Th(nth, f), 235U(n3 MeV, f) and 252Cf(s, f). Together with those previously obtained [233, 235U(nth, f) and 239, 241Pu(nth, f] the results show that these charge distributions depend very sensitively on both the fissioning species and the initial excitation energy. Very strong even-odd effects are present, for example in the charge distribution of 229Th(nth, f) while they almost disappear in 235U(n3 MeV, f). In the 229Th(nth f) and 252Cf(s, f) cases, kinetic energy distributions of the fragments have been obtained. Fragments with even charges are more energetic, on average, than fragments with odd charges. The results are discussed in terms of a rather small probability for pair breaking during the transition from saddle-point to scission. The relationship between even-odd effects in charge distributions and fine structures in mass distributions is also investigated.

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  • Cited by (0)

    This work is part of the thesis of Ch. Hamelin (radiochemical measurements) and of G. Mariolopoulos (EE measurements).

    ††

    Also at: Université Scientifique et Médicale de Grenoble, France

    ††

    Also at: Institut Laue-Langevin, Grenoble, France

    Also at: Institut Laue-Langevin, Grenoble, France.

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