The fusion–fission and quasi-fission processes in the reaction 48Ca + 208Pb at energies near the Coulomb barrier

✍ Scribed by E.V. Prokhorova; A.A. Bogachev; M.G. Itkis; I.M. Itkis; G.N. Knyazheva; N.A. Kondratiev; E.M. Kozulin; L. Krupa; Yu.Ts. Oganessian; I.V. Pokrovsky; V.V. Pashkevich; A.Ya. Rusanov

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 928 KB
• Volume: 802
• Category: Article
• ISSN: 0375-9474
• DOI: 10.1016/j.nuclphysa.2008.01.016

✦ Synopsis

Mass-energy distributions (MEDs) and capture-fission cross sections have been measured in the reaction 48 Ca + 208 Pb → 256 No at the energies E lab = 206-242 MeV using a double-arm time-of-flight spectrometer CORSET. It has been observed that MED of the fragments consists of two parts, namely, the classical fusion-fission process corresponding to the symmetric fission of 256 No and quasi-fission "shoulders" corresponding to the light fragment masses ∼ 60-90 u and complimentary heavy fragment masses. The quasi-fission "shoulders" have a higher total kinetic energy (TKE) as compared with that expected for the classical fission. A mathematical formalism was employed for the MEDs fragment decomposition into fusion-fission and quasi-fission components. In the fusion-fission process a high-energy Super-Short mode has been discovered for the masses M H = 130-135 u and the TKE of ≈ 233 MeV.