Quasi-fission and other strongly damped collisions between 63Cu ions and 197Au nuclei

doi:10.1016/0375-9474(77)90424-9

Nuclear Physics A

Volume 279, Issue 1, 21 March 1977, Pages 110-124

https://doi.org/10.1016/0375-9474(77)90424-9 Get rights and content

Abstract

The interaction of ⁶³Cu ions with ¹⁹⁷Au nuclei have been studied experimentally at incident energies of 365 and 443 MeV (1.1 and 1.4 times the Coulomb barrier). Mass and kinetic energy distributions of reaction products have been measured at several angles. Near the grazing angle, a continuous transition was found from elastic events to partially damped (PD) events, and to fully damped events (quasi-fission, QF). Away from the grazing angle a clean separation between elastic and QF events was observed. Events that may be due to fission following fusion (CF) were also obtained. Results are discussed in terms of decomposition into PD, QF, and CF components. The QF kinetic energy is independent of the incident energy (implying full damping of the initial relative motion). It is lower than the Coulomb barrier and close to the kinetic energies from the fission of similar systems. The angular distribution is peaked somewhat forward of the grazing angle for low mass transfers. For large mass transfers the yield increases slowly with decreasing angle. At 443 MeV a large contribution from negative angles is present. σ_QF accounts for more than 65 % of the reaction cross section σ_R at 443 MeV and for more than 50 % at 365 MeV. The upper limit on CF is about 10 % of σ_R, and σ_PDis of the order of 25 % of σ_R.

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IPN ORSAY report IPNO-RC-75-08

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Citation Excerpt :
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^†: Present address: Oak Ridge National Laboratory, Oak Ridge, TN 37830, USA.

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Nuclear Physics A

Quasi-fission and other strongly damped collisions between 63Cu ions and 197Au nuclei

Abstract

Nucl. Phys.

Nucl. Instr.

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Phys. Lett.

Phys. Rev. Lett.

Phys. Rev. Lett.

Phys. Rev. Lett.

IPN ORSAY report IPNO-RC-75-08

Fusion hindrance and roles of shell effects in superheavy mass region

New ion-guide for the production of beams of neutron-rich nuclei between Z=20-28

Quasi-elastic reaction cross sections and the merging instability

Fusion and capture of heavy ions above the barrier: Analysis of experimental data with the surface friction model

The interaction of 605 MeV <sup>63</sup>Cu with <sup>197</sup>Au

Gamma ray multiplicities in deep inelastic collisions for the Cu + Au 400 MeV system

Quasi-fission and other strongly damped collisions between ⁶³Cu ions and ¹⁹⁷Au nuclei