Abstract
We have studied mass-energy distributions (MED) of fission fragments using two projectile-target combinations, 12C + 204Pb and 48Ca + 168Er, leading to the same compound nucleus 216Ra at the excitation energy E*∼40 MeV. It has been found that the contribution of the asymmetric mode in the case of the former reaction is 1.5%, and it is 30% in the case of the latter one. We connect such a sharp increase in the yield of asymmetric products in the 48Ca + 168Er reaction with the quasifission process, the MED of which have a clearly expressed shell structure. The characteristics of the fission fragment MED are of such a kind that they can be interpreted by analogy with the low-energy fission of heavy nuclei as a manifestation of an independent mode of nuclear decay which competes with the classical fusion-fission process.
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From Yadernaya Fizika, Vol. 66, No. 6, 2003, pp. 1234–1239.
Original English Text Copyright © 2003 by Pokrovsky, Chizhov, M. Itkis, I. Itkis, Kniajeva, Kozulin, Kondratiev, Sagaidak, Voskressensky, Corradi, Stefanini, Trotta, Vinodkumar, Beghini, Montagnoli, Scarlassara, Rusanov, Hanappe, Dorvaux, Rowley, Stuttgé.
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Pokrovsky, I.V., Chizhov, A.Y., Itkis, M.G. et al. The effect of the entrance channel on the fission of 216Ra. Phys. Atom. Nuclei 66, 1198–1202 (2003). https://doi.org/10.1134/1.1586437
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DOI: https://doi.org/10.1134/1.1586437