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The fusion cross sections and barrier distributions of stable Zr isotope targets 90,92,94,96Zr with 30Si projectile nuclei are investigated theoretically via the Energy-dependent Woods-Saxon Potential (EDWSP) and Coupled Channel (CC) models. In our calculations, we have taken the bombarding energy range of the projectile-target interaction to be around the Coulomb barrier for all reactions. All theoretical accounts have been worked via the NRV Knowledge Base, the CCFULL code, and Wong's formula. We detailed interrogated the repercussions of phonon number in projectile and target nuclei on heavy-ion fusion cross sections and barrier distributions. Over this investigation, we presented that the EDWSP and CC models, and all computation bases operated to elucidate the fusion cross-section data and barrier distributions are decent. Our theoretical investigation proves the importance of inspecting heavy-ion fusion reactions with theory-based research and encourages new experimental investigations that are not yet included in the literature.

The nucleon density distributions and the nucleus-nucleus interaction potentials have been calculated for the 16O + 208Pb and 12C + 208Pb reactions using the modified Thomas–Fermi method, in which all terms up to h2-ones in the quasiclassical series expansion of the kinetic energy are taken into account. Skyrme forces depending on the nucleon density are used as the nucleon-nucleon interaction. On the basis of the obtained potentials, the cross-sections of subbarrier fusion and elastic scattering are calculated and agree well with the latest experimental data., Густини розподiлу нуклонiв та потенцiали мiжядерної взаємодiї для реакцiй 16O + 208Pb та 12C + 208Pb було розраховано в рамках модифiкованого методу Томаса–Фермi, з урахуванням усiх доданкiв до членiв другого порядку по h у квазiкласичному розкладi кiнетичної енергiї. В ролi нуклон-нуклонної взаємодiї використовувалися сили Скiрма, залежнi вiд густини нуклонiв. На основi одержаних потенцiалiв були обчисленi перерiзи пiдбар’єрного злиття та пружного розсiяння, що добре узгоджуються з новiтнiми експериментальними даними.

The fusion process is the effect of a one-dimensional barrier penetration model that incorporates scattering potential as a combination of Coulomb and proximity potentials. Heavy-ion fusion reactions were performed with coupled-channel (CC) calculations. In heavy-ion fusion reactions, CC formalism is carried through the under-barrier energy. Here, fusion cross sections were calculated and investigated for the O-16+Ge-70,Ge-72,Ge-74,Ge-76, O-16+Sm-148,Sm-150,Sm-152,Sm-154, Ne-20+Zr-90,Zr-92,Zr-94,Zr-96, Ne-20+Sn-112,Sn-114,Sn-116,Sn-118,Sn-120, Si-28+Mo-90,Mo-96, Si-28+Mg-24,Mg-26, Si-28+Ni-58,Ni-64, Si-28+Zr-90,Zr-94,Zr-96, S-32+Zr-90,Zr-96, S-36+Pb-204,Pb-206,Pb-208,Pb-210, Ar-40+Hf-176,Hf-178,Hf-180 in the framework of CC calculations (CCFULL, NRV) and Wong's formula. Fusion cross sections were analyzed in detail by CC calculations considering 2(+) and 3(-) excitation modes for the projectile and the target. The calculated cross-section results were compared with the experimental data. The calculations were found to produce reliable data compared to experimental data. Fusion barrier distributions (D-fus) for all reactions have been investigated below and above the Coulomb barrier using the coupled-channel method with CCFULL, NRV codes and second derivative of Wong's formula. The harmony among these calculations was examined and it was determined that the models were in harmony with each other.

$\textit{Background}$: Nuclear fusion has been shown to be a perfect probe to study the different nuclear shapes. However, the possibility of testing octupole deformation of a nucleus with this tool has not been fully explored yet. The presence of a stactic octupole deformation in nuclei will enhanced a possible permanent electric dipole moment, leading to a possible demonstration of parity violation. $\textit{Purpose}$: To check whether static octupole deformation or octupole vibration in fusion give qualitatively different results so that both situations can be experimentally disentangled. $\textit{Method}$: Fusion cross sections are computed in the Coupled-Channels formalism making use of the Ingoing-Wave Boundary Conditions (IWBC) for the systems $^{16}$O+$^{144}$Ba and $^{16}$O+$^{224}$Ra. $\textit{Results}$: Barrier distributions of the two considered schemes show different patterns. For the $^{224}$Ra case, the octupole deformation parameter is large enough to create a sizeable difference. $\textit{Conclusions}$: The measurement of barrier distributions can be an excellent probe to clarify the presence of octupole deformation., Comment: Important changes from previous version, 6 pages, 5 figures, 2 tables, submitted to Phys. Rev. C

We studied the elastic scattering process for the system (17)F + (58)Ni at two colliding energies slightly above the Coulomb barrier. The experimental data were analyzed within the framework of the optical model to investigate the effects of the projectile small binding energy (S(p) = 600 keV) on the reaction dynamics. We found that in this energy range the "reduced" reaction cross section for the system (17)F + (58)Ni is rather similar to that induced by the interaction of tightly-bound (16)O nuclei on the same target. Nuclear Physics A

Exclusive alpha-particle and proton production measurements of the system (6)Li+(28)Si are performed at near-barrier energies. Each reaction channel is tagged via a particle-gamma coincidence requirement. Ratios of direct to compound contributions are estimated via particle angular distribution measurements. Strong reaction channels for n and p transfer are identified and quantified and found to be described well on a qualitative basis with distorted-wave Born approximation calculations. Physical Review C

The effect of Li-6 and He-6 breakup on the fusion cross section of these nuclei with Pb-208 is investigated by means of continuum-discretized coupled-channels (CDCC) calculations. For Li-6 the calculations describe reasonably well the experimental data for elastic scattering, Li-6-->alpha+d breakup and the absorption cross section given by the sum of the Li-6 fusion and the alpha production cross section not attributed to breakup. The effect of Li-6 breakup on the calculated absorption cross section is found to depend strongly on the imaginary part of the diagonal bare potential. A combination of the CDCC technique and the barrier penetration model generates results close to the measured fusion cross section. For He-6 the calculated absorption cross section is much larger than the measured He-6+Bi-209 complete fusion cross section values. However, it is found to be relatively independent of the form of the imaginary part of the bare potential. The complete fusion cross section is again found to be reasonably well described by the CDCC/BPM combination. Physical Review C

The elastic scattering of Li-6 and He-6 by Pb-208 at energies in the vicinity of the Coulomb barrier is studied by means of continuum-discretized coupled-channels calculations. It is shown that the strong reduction of the He-6+Pb-208 elastic scattering cross section at forward angles is caused by long-range dipole Coulomb excitation of the projectile. The role of breakup in the fusion of halo nuclei is also discussed. ispartof: Physical Review C vol:67 issue:4 pages:041604-1 status: published

The effect of breakup in the fusion cross section in terms of suppression versus enhancement, discussed in a conflicting way in the literature is addressed. Data and theoretical predictions available in the literature are compared. Excitation functions of the sub- and near-barrier fusion cross-sections for a wide variety of light and heavy systems are presented and interpreted. We have measured fusion excitation functions and breakup correlation functions for the medium weight systems 6 Li + 59 Co and 7 Li + 59 Co. These measurements help to establish the influence of the projectile breakup on the fusion process at near-barrier energies and contribute to the determination of how the mass of the target affects the breakup role. The results indicate a light fusion enhancement at sub-barrier energies and a geometry dominated cross section at barrier energies.

Excitation functions for sub- and near-barrier total (complete + incomplete) fusion cross sections are presented for the 6, 7Li+59-Co reactions. Evaporation residues were identified by their characteristic gamma rays and the corresponding yields measured with both the IReS Garel + array at the Vivitron facility and with the Sao Paulo Ge array at the 8UD Pelletron tandem facility using standard gamma-ray techniques. The data extend to medium-mass systems previous works exploring the coupling effects (hindrance versus enhancement) in fusion reactions of both lighter and heavier systems. The results indicate a small enhancement of total fusion for the more weakly bound 6Li at sub- barrier energies, with similar cross sections for both reactions at and above the barrier.

The near-barrier and sub-barrier fusion of light unstable nuclei and their respective stable isotopes with heavy targets ${(}^{4,6}\mathrm{He}{+}^{209}\mathrm{Bi},$ ${}^{4,6}\mathrm{He}{+}^{238}\mathrm{U},$ ${}^{9,11}\mathrm{Be}{+}^{209}\mathrm{Bi},$ and ${}^{9}\mathrm{Be}{+}^{208}\mathrm{Pb})$ is investigated via coupled channel calculations. The entrance channel optical potential is generated via a microscopic BDM3Y1 interaction. A rather satisfactory description of the experimental data is obtained under the condition that the real part of the optical potential has to be reduced for the weakly bound and halo systems. This reduction proves to be the fundamental difference in treating stable and weakly bound nuclei, and can be attributed to the loss of a flux due to breakup effects.

A representation of the fusion barrier distributions has been deduced from the back angle quasielastic scattering cross section data in O-1618+ Sn-12,Sn-124 reactions, measured over a wide range of bombarding energies around the Coulomb barrier. The results have been compared with coupled channel calculations using the CCDEF code to study the effects of projectile and target inelastic excitations and nucleon transfer couplings on the representation of fusion barrier distributions in these systems. The present studies bring out the importance of coupling of 2n pickup in the O-16+ Sn-120,Sn-124 reactions and 2n stripping in the O-18+ Sn-120,Sn-124 reactions in explaining the observed barrier distributions.