Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userDinuclear concept - cluster model of fusion
56
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
The synthesis of superheavy elements is analysed within the dinuclear system concept of compound nucleus formation. The perspectives for using radioactive beams in complete fusion reactions are discussed.
rate research
Read More
Within the dinuclear system (DNS) conception, instead of solving Fokker-Planck Equation (FPE) analytically, the Master equation is solved numerically to calculate the fusion probability of super-heavy nuclei, so that the harmonic oscillator approximation to the potential energy of the DNS is avoided. The relative motion concerning the energy, the angular momentum, and the fragment deformation relaxations is explicitly treated to couple with the diffusion process, so that the nucleon transition probabilities, which are derived microscopically, are time-dependent. Comparing with the analytical solution of FPE, our results preserve more dynamical effects. The calculated evaporation residue cross sections for one-neutron emission channel of Pb-based reactions are basically in agreement with the known experimental data within one order of magnitude.
The influence on the fusion process of coupling transfer/breakup channels is investigated for the medium weight $^{6,7}$Li+$^{59}$Co systems in the vicinity of the Coulomb barrier. Coupling effects are discussed within a comparison of predictions of the Continuum Discretized Coupled-Channels model. Applications to $^{6}$He+$^{59}$Co induced by the borromean halo nucleus $^{6}$He are also proposed.
We investigate the $alpha$+oo cluster structure in the inversion-doublet band ($K^pi=0_{1}^pm$) states of ene with an angular-momentum-projected version of the Tohsaki-Horiuchi-Schuck-R{o}pke (THSR) wave function, which was successful in its original form for the description of, e.g., the famous Hoyle state. In contrast with the traditional view on clusters as localized objects, especially in inversion doublets, we find that these {it single} THSR wave functions, which are based on the concept of nonlocalized clustering, can well describe the $K^{pi}=0_1^-$ band and the $K^{pi}=0_1^+$ band. For instance, they have 99.98% and 99.87% squared overlaps for $1^-$ and $3^- $ states (99.29%, 98.79% and 97.75% for $0^+, 2^+$ and $4^+$ states), respectively, with the corresponding exact solution of the $alpha$+oo resonating group method. These astounding results shed a completely new light on the physics of low energy nuclear cluster states in nuclei: The clusters are nonlocalized and move around in the whole nuclear volume, only avoiding mutual overlap due to the Pauli blocking effect.
Potential energies, moments of inertia, quadrupole and octupole moments of dinuclear systems are compared with the corresponding quantities of strongly deformed nuclei. As dinuclear system we denote two touching nuclei (clusters). It is found that the hyperdeformed states of nuclei are close to those of nearly symmetric dinuclear systems, whereas the superdeformed states are considered as states of asymmetric dinuclear systems. The superdeformed and hyperdeformed states constructed from two touching clusters have large octupole deformations. The experimental measurement of octupole deformation of the highly deformed nuclei can answer whether these nuclei have cluster configurations as described by the dinuclear model.
A variety of phenomena connected with the formation of a dinuclear complex is observed in the heavy ion collisions at low energies. The dinuclear system model allows us to analyze the experimental data and to interpret them by comparison of the partial capture, fusion and evaporation residue cross sections measured for the different reactions leading to the same compound nucleus. The comparison of theoretical and experimental values of the mass and angular distributions of the reaction products gives us a detailed information about reaction mechanism forming the observed yields. The observed very small cross sections of the evaporation residues may be explained by the strong fusion hindrance and/or instability of the heated and rotating compound nucleus and smallness of its survival probability. The fusion hindrance arises due to competition between complete fusion and quasifission while the smallness of survival probability is connected with the decrease of the fission barrier at large excitation energy and angular momentum of compound nucleus.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
