Continuum Discretized Coupled-Channel(CDCC) model calculations of total, complete and incomplete fusion cross sections for reactions of the weakly bound ~6Li with ^(144,154)Sm targets at energies around the Coulomb barrier are presented. In the cluster structure frame of ~6Li→α+d, short-range absorption potentials are considered for the interactions between the ground state of the projectile ~6Li and α-d fragments with the target. In order to separately calculate complete and incomplete fusion and to reduce double-counting, the corresponding absorption potentials are chosen to be of different range. Couplings to low-lying excited states 2^+, 3^-of ^(144)Sm and 2^+, 4^+ of ^(154)Sm are included. So, the effect on total fusion from the excited states of the target is investigated. Similarly, the effect on fusion due to couplings to resonance breakup states of ~6Li, namely, l = 2,J~π= 3^+, 2^+, 1^+ is also calculated.The latter effect is determined by using two approaches,(a) by considering only resonance state couplings and(b)by omitting these states from the full discretized energy space. Among other things, it is found that both resonance and non-resonance continuum breakup couplings produce fusion suppression at all the energies considered.
A theoretical evaluation of the collective excitation spectra of nucleus at large deformations is possible within the framework of the dinuclear system(DNS) model, which treats the wave function of the fissioning nucleus as a superposition of a mononucleus configuration and two-cluster configurations in a dynamical way, permitting exchange of nucleons between clusters. In this work the method of calculation of the potential energy and the collective spectrum of fissioning nucleus at scission point is presented. Combining the DNS model calculations and the statistical model of fission we calculate the angular distribution of fission fragments for the neutron–induced fission of239 Pu.
The high-spin rotational properties of two-quasiparticle bands in the doubly-odd ^(166)Ta are analyzed using the cranked shell model with pairing correlations treated by a particle-number conserving method, in which the blocking effects are taken into account exactly. The experimental moments of inertia and alignments and their variations with the rotational frequency ω are reproduced very well by the particle-number conserving calculations, which provides a reliable support to the configuration assignments in previous works for these bands. The backbendings in these two-quasiparticle bands are analyzed by the calculated occupation probabilities and the contributions of each orbital to the total angular momentum alignments. The moments of inertia and alignments for the Gallagher-Moszkowski partners of these observed two-quasiparticle rotational bands are also predicted.
The nuclear dynamical deformation,the fusion probability and the evaporation residue(ER) cross sections for the synthesis of superheavy nuclei are studied with the di-nuclear system model and the related dynamical potential energy surface.The intrinsic energy and the maximum dynamical deformations for48Ca+248Cm are calculated.The effect of dynamical deformation on the potential energy surface and fusion is investigated.It is found that the dynamical deformation influences the potential energy surface and fusion probability significantly.The dependence of the fusion probability on the angular momentum is investigated.The ER cross sections for some superheavy nuclei in48Ca induced reactions are calculated and it is found that the theoretical results are in good agreement with the experimental results.
The recently observed two high-spin rotational bands in the proton emitter ^(113)Cs are investigated using the cranked shell model with pairing correlations treated by a particle-number conserving method, in which the Pauli blocking effects are taken into account exactly. By using the configuration assignments of band 1 [π3/2^+[422](g_(7/2)), α =-1/2] and band 2 [π1/2^+[420](d_(5/2)), α=1/2], the experimental moments of inertia and quasiparticle alignments can be reproduced much better by the present calculations than those using the configuration assginment of π1/2^-[550](h_(11/2)), which in turn may support these configuration assignments. Furthermore, by analyzing the occupation probability nμ of each cranked Nilsson level near the Fermi surface and the contribution of each orbital to the angular momentum alignments, the backbending mechanism of these two bands is also investigated.
Ground state properties for Mg isotopes,including binding energies,one- and two-neutron separation energies,pairing energies,nuclear matter radii and quadrupole deformation parameters,are obtained from the selfconsistent relativistic mean field(RMF) model with the pairing correlations treated by a shell-mode-like approach(SLAP),in which the particle-number is conserved and the blocking effects are treated exactly.The experimental data,including the binding energies and the one- and two-neutron separation energies,which are sensitive to the treatment of pairing correlations and block effects,are well reproduced by the RMF+SLAP calculations.
The role of tensor force on the collision dynamics of16O+16O is investigated in the framework of a fully three-dimensional timedependent Hartree-Fock theory.The calculations are performed with modern Skyrme energy functional plus tensor terms.Particular attention is given on the analysis of dissipation dynamics in heavy-ion collisions.The energy dissipation is found to decrease as an initial bombarding energy increases in deep-inelastic collisions for all the Skyrme parameter sets studied here because of the competition between the collective motion and the single-particle degrees of freedom.We reveal that the tensor forces may either enhance or reduce the energy dissipation depending on the different parameter sets.The fusion cross section without tensor force overestimates the experimental value by about 25%,while the calculation with tensor force T11 has good agreement with experimental cross section.
The conventionally separated treatments for strangelets and strange stars are now unified with a more comprehensive theoretical description for objects ranging from strangelets to strange stars. After constraining the model parameter according to the Witten–Bodmer hypothesis and observational mass–radius probability distribution of pulsars, we investigate the properties of this kind of objects. It is found that the energy per baryon decreases monotonically with increasing baryon number and reaches its minimum at the maximum baryon number, corresponding to the most massive strange star. Due to the quark depletion,an electric potential well is formed on the surface of the quarkpart. For a rotational bare strange star, a magnetic field with the typical strength in pulsars is generated.
