2017/10/02 by B. Schuetrumpf, Bastian Schuetrumpf, W. Nazarewicz +1 · 1 citation
Physics and Astronomy · #Advanced Chemical Physics Studies #Astronomical and nuclear sciences #Atomic physics #Cluster (spacecraft) #Coulomb explosion #Excited state #Ion #Ionization #Mirror nuclei #Nuclear physics #Nuclear physics research studies #Nucleon #Physics #Time-dependent density functional theory #nucl-th
paper · pdf · doi:10.1103/physrevc.96.064608
published as Phys. Rev. C 96, 064608 (2017) · 10 pages, 8 figures
arxiv created 2017/10/02 · openalex publication_date 2017/12/15 · arxiv updated 2017/12/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Background: Applications of nuclear time-dependent density functional theory (TDDFT) are often capable of providing quantitative description of heavy ion reactions. However, the structure of pre-compound states produced in heavy ion reactions are difficult to assess theoretically in TDDFT as the s.p. density alone is a weak indicator of shell structure and cluster states. Purpose: We employ the time-dependent nucleon localization function (NLF) to reveal structure of pre-compound states in nuclear reactions involving light and medium-mass ions. We primarily focus on spin saturated systems with N = Z. Furthermore, we study reactions with oxygen and carbon ions, for which experimental evidence for α clustering in pre-compound states exists. Method: We utilize the symmetry-free TDDFT approach and compute the NLFs to describe 16O + 16O, 40Ca + 16O, 40Ca + 40Ca, and 16,18O + 12C collisions at energies above the Coulomb barrier. Results: We show that NLFs reveal a variety of time-dependent modes involving cluster structures. For instance, the 16O + 16O collision results in a vibrational mode of a quasi-molecular α-12C-12C-α state. For heavier ions, a variety of cluster configurations are predicted. For the collision of 16,18O + 12C, we showed that the pre-compound system has a tendency to form α clusters. This result supports the experimental findings that the presence of cluster structures in the projectile and target nuclei gives rise to strong entrance channel effects and enhanced α emission. Conclusion: The time-dependent NLF is a good indicator of clusters structures in complex pre-compound states formed in heavy-ion fusion reactions. The localization reveals the presence of collective vibrations involving cluster structures, which dominate the initial dynamics of the fusing system.