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arXiv · 1409.3277

Dissipative dynamics in quasi-fission

V. E. Oberacker·A. S. Umar·C. Simenel
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Abstract

Quasi-fission is the primary reaction mechanism that prevents the formation of superheavy elements in heavy-ion fusion experiments. Employing the time-dependent density functional theory approach we study quasi-fission in the systems $^{40,48}$Ca+$^{238}$U. Results show that for $^{48}$Ca projectiles the quasi-fission is substantially reduced in comparison to the $^{40}$Ca case. This partly explains the success of superheavy element formation with $^{48}$Ca beams. For the first time, we also calculate the repartition of excitation energies of the two fragments in a dynamic microscopic theory. The system is found in quasi-thermal equilibrium only for reactions with $^{40}$Ca. The differences between both systems are interpreted in terms of initial neutron to proton asymmetry of the colliding partners.

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V. E. Oberacker, A. S. Umar, C. Simenel. 2014-09-10. Dissipative dynamics in quasi-fission. https://doi.org/10.1103/physrevc.90.054605

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