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A model-independent irreducible tensor approach is presented for the np fusion reaction. Appropriate spin-observables are identified to determine empirically the initial spin singlet and triplet contributions to the differential cross-section, in view of the recent experimental interest in studying radiative capture of polarized neutrons by polarized protons.

Using a nucleon–nucleon force of the type M3Y-Reid and an additional repulsive interaction which simulates the incompressibility effects of the nuclear matter, we have examined the effects of the repulsive core modeling on the interaction potentials and complete fusion cross-sections for ⁹Be + ¹²⁴Sn and ⁹Be + ⁸⁹Y systems. The adjusted parameters of this repulsive force have been chosen in such a way that fully explains the properties of the nuclear matter in the region where the nuclear densities of the interacting nuclei completely overlap. The results of our studies reveal that accounting for this correction in the calculations of the total potentials leads to improvement of calculated cross-sections and affects on the complete fusion suppression at above barrier energies.

Analysis of the fusion reactions of halo nuclei is one of the important subjects of nuclear physics. In addition, temperature-dependent analysis of fusion cross-sections of these nuclei is a deficient topic in the literature. In order to overcome this deficiency, the fusion cross-sections of ⁶He, ⁸He and ${}^{11}$Li which are the most important halo nuclei are analyzed by using both temperature-independent potential and temperature-dependent potential. All the theoretical results are compared with each other as well as the experimental data. It is seen that the results of temperature-independent potential are in good agreement with the data while the temperature-dependent potential has a significant impact on the fusion cross-sections. Finally, the changes with the temperature of both real and nuclear potentials of all the reactions are investigated.

This paper presents results of the application Monte Carlo method to analyze data from the interaction of deuteron beams with metallic targets saturated with deuterium. The SRIM software was used to generate energy spectrum of ions passing the target. These spectra were used to calculate the neutron yields from dd reactions in energy range 7–12 keV of incident deuteron beams. The calculated outputs were compared with the experimental data for the determination of the electron screening potential for dd reactions. The calculations were performed using two different values of the beam energy spread (FWHM) equal 1% and 16%. It was shown that plasma beams with a relatively high spread (16%) were almost as good a tool as the traditional accelerator with mono-energy beam related to the study of the reaction within an ultra-low energy region.

The fusion dynamics of ${}^{30}\mathrm{\text{Si}}+{}^{238}\mathrm{\text{U}}$ reaction has been studied using different theoretical approaches like energy-dependent Woods–Saxon potential (EDWSP) model, coupled channel formulation and Wong approach. At sub-barrier energies, the anomalously large enhancement of the fusion cross-section signifies the importance of barrier modification effects for the adequate addressal of experimental data. The EDWSP model, wherein barrier modification effects are introduced via the energy-dependent diffuseness parameter, is used to examine the sub-barrier fusion anomalies. In the framework of coupled channel model, the impacts of collective excitations and/or static deformations of colliding partners are incorporated in the fusion dynamics. In Wong formula, the role of different Skyrme forces such as SIII, KDE0v1, SkT1, SSk, GSkI is analyzed to address the observed fusion enhancement around the Coulomb barrier. Among these, GSkI and SSk forces seem more appropriate for the addressal of fusion dynamics at sub-barrier energies while SIII, SkT1 and KDE0v1 forces give relatively better results at the above barrier region. The SSk (GSkI) force at higher energies overestimate the experimental data and hence treated with the $\ell$-summed Wong approach. The effect of deformations and optimum orientations is duly incorporated in the calculation and hence gives better description to the observed data. In addition, the fusion cross-sections are predicted over extreme energies using EDWSP and $\ell$-summed Wong approach. It is worth mentioning here that the different theoretical approaches (EDWSP, coupled channel and Wong) induce similar kinds of barrier lowering effects, henceforth, they reasonably describe the sub-barrier fusion data of ${}^{30}\mathrm{\text{Si}}+{}^{238}\mathrm{\text{U}}$ reaction.

We study the low-energy $d+t\to n+\alpha$ fusion reaction using a model inspired by the halo/cluster effective field theory (H/CEFT) formalism. For this purpose, we initially focus on the $d+t\to n+\alpha$ reaction without considering the Coulomb force in the incoming deuteron–triton system. In the next step, we insert the Coulomb correction in the $d+t\to n+\alpha$ cross-section. The cross-section results involve unknown parameters. So, finally, we fit the H/CEFT cross-section of the $d+t\to n+\alpha$ reaction to the experimental data and obtain the values of these unknown parameters.

The fusion evaporation residue (ER) cross-sections ${\sigma }_{xn}$ for the decay of compound nucleus (CN) ${}^{252,254,255,256}$No${}^{\ast }$ via 1$n$–4$n$ decay channels, synthesized in ${}^{204,206,207,208}$Pb$+$${}^{48}$Ca reaction, are studied, including deformations ${\beta }_{2i}$ for cold-optimum orientations ${𝜃}_i$ at various ${}^{48}$Ca excitation energies of $E^{\ast }=20$ to 45MeV. For the nuclear interaction potentials, we use the Skyrme energy density functional (SEDF)-based on semi-classical extended Thomas Fermi (ETF) approach under frozen density approximation on our earlier study of fusion ER cross-section for the decay of ${}^{252,254-256}$No${}^{\ast }$, via 1$n$–4$n$ decay channels synthesized in ${}^{204,206-208}$Pb$+$${}^{48}$Ca reaction based on the Dynamical cluster-decay model (DCM) using the pocket formula for nuclear proximity potential in which the above reaction was investigated by using hot-optimum orientations. In this work the above reaction has been investigated in two parts, in the first part, $E^{\ast }<25$MeV is used for cold elongated configurations and in the second part, $E^{\ast }>25$MeV is used for hot compact configurations. The Skyrme forces used here are the old SIII, and new GSkI and KDE0(v1) given for both normal and isospin-rich nuclei, with densities added in frozen density approximation. Interestingly, independent of the Skyrme force used, the DCM gives an excellent fit within one-parameter fitting of $\mathrm{\Delta }R$ to the measured data on fusion ER for cold fusion. Of all the three Pb-isotopes and three $E^{\ast }$ considered, at each $E^{\ast }$, the $\mathrm{\Delta }R$ is largest for compound system with mass numbers 256 and 254, and smallest for 252, which means that the neutrons emission occur earliest for 256, then 255 followed by 254 and finally for 252, in complete agreement with experimental data. The possible fusion–fission (ff) and quasi-fission (qf) mass-regions of fragments on DCM are also predicted. The DCM with Skyrme forces is further used to look for all the possible target-projectile ($t$-$p$) combinations forming the “cold” CN ${}^{254}$No${}^{\ast }$ at the CN excitation energy of $E^{\ast }$ for “optimum cold” configurations. The fusion ER cross-sections, for the proposed new reactions in synthesizing the CN ${}^{254}$No${}^{\ast }$, are also estimated for the future experiments.

Fusion cross sections induced by ^4,6,8He and ⁷Li were studied using different reactions [(⁴He+²⁰⁹Bi, ⁴He+²⁰⁸Pb, ⁴He+¹⁹⁷Au), (⁶He+²⁰⁹Bi, ⁶He+²⁰⁶Pb, ⁶He+¹⁹⁷Au) and (⁸He+²⁰⁹Bi, ⁸He+²⁰⁴Pb, ⁸He+¹⁹⁷Au)], these reactions were used to determine the influence of the heavy targets on the fusion excitation function mechanism. The reactions [⁴He+²⁰⁸Pb, ⁶He+²⁰⁶Pb, ⁸He+²⁰⁴Pb] give the same compound nuclei ²¹²Po and the reactions (⁶He+²⁰⁹Bi and ⁷Li+²⁰⁸Pb) give the same compound nuclei ²¹⁵At. These reactions were used to determine the influence of the compound nuclei on fusion excitation function mechanism. Theoretical calculations were done using the Channel Coupling code of the NRV using W. S. Surface with different parameters (V_o, r_o, ^Colr_o, a and ћωβ) for all reactions. The current study has shown that, large enhancement in the fusion cross sections at energies at the Coulomb barrier were observed only in the reactions ⁶He+²⁰⁶Pb and ⁸He+²⁰⁴Pb compared with ⁴He+²⁰⁸Pb and slightly or no enhancement were observed in the reactions ^6,8He+²⁰⁹Bi and ^6,8He+¹⁹⁷Au compared with reactions induced by ⁴He.