Fusion process studied with preequilibrium giant dipole resonance in time dependent Hartree-Fock theory

Abstract

The equilibration of macroscopic degrees of freedom during the fusion of heavy nuclei, like the charge and the shape, are studied in the Time-Dependent Hartree-Fock theory. The pre-equilibrium Giant Dipole Resonance (GDR) is used to probe the fusion path. It is shown that such isovector collective state is excited in N/Z asymmetric fusion and to a less extent in mass asymmetric systems. The characteristics of this GDR are governed by the structure of the fused system in its preequilibrium phase, like its deformation, rotation and vibration. In particular, we show that a lowering of the pre-equilibrium GDR energy is expected as compared to the statistical one. Revisiting experimental data, we extract an evidence of this lowering for the first time. We also quantify the fusion-evaporation enhancement due to gamma-ray emission from the pre-equilibrium GDR. This cooling mechanism along the fusion path may be suitable to synthesize in the future super heavy elements using radioactive beams with strong N/Z asymmetries in the entrance channel.

15 pages, 19 figures, revised version

Cited by in corpus (18)

• Energy dependence of nucleus-nucleus potential close to the Coulomb barrier
• TDHF Theory and Its Extensions for the Multinucleon Transfer Reaction: a Mini Review
• Collision dynamics of two ${}^{238}$U atomic nuclei
• Pairing Vibrations Study with the Time-Dependent Hartree-Fock-Bogoliubov theory
• Microscopic study of Ca$+$Ca fusion
• Enhanced nucleon transfer in tip collisions of ${}^{238}$U+${}^{124}$Sn
• Time-Depentent Hartree-Fock description of heavy ions fusion
• Neutron Transfer Dynamics and Doorway to Fusion in Time-Dependent Hartree-Fock Theory
• Dependence of fusion on isospin dynamics
• The Dynamical Dipole Mode in Fusion Reactions with Exotic Nuclear Beams
• Evidence for the role of proton shell closure in quasi-fission reactions from X-ray fluorescence of mass-identified fragments
• Symmetry Energy Effects on Fusion Cross Sections
• Mass dispersions from giant dipole resonances using the Balian-Veneroni variational approach
• Nucleon exchange in heavy-ion collisions within stochastic mean-field approach
• Challenges in description of heavy-ion collisions with microscopic time-dependent approaches
• Nuclear Quantum Many-Body Dynamics: From Collective Vibrations to Heavy-Ion Collisions (2nd edition)
• Microscopic approaches for nuclear Many-Body dynamics: applications to nuclear reactions
• Microscopic quasifission dynamics of the ${}^{54}\text{Cr}+{}^{243}\text{Am}$ reaction