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[en] We present a simultaneous analysis of the elastic scattering and fusion cross-section data of the ¹²C + ²⁴Mg system around the Coulomb barrier and over energies by using the microscopic α-α double folding cluster potential within the framework of the optical model and the coupled-channels formalism. The α-α double folding cluster potential is obtained by using the α-cluster distribution densities of the nuclei in the usual double folding procedure. The microscopic potential results are compared with the findings of the phenomenological deep and shallow potentials. It is subsequently shown that only phenomenological deep, real, microscopic nucleon-nucleon and α-α double folding cluster potentials provide a consistent description of the angular distributions and fusion cross-section data simultaneously. The effect of the inclusion of the excited states of the target nucleus ²⁴Mg on the fusion cross-section predictions is also determined by the coupled-channels calculations, which are shown to improve the agreement

[en] A simple exact analytical solution of the relativistic Duffin-Kemmer-Petiau equation within the framework of the asymptotic iteration method is presented. Exact bound state energy eigenvalues and corresponding eigenfunctions are determined for the relativistic harmonic oscillator as well as the Coulomb potentials. As a nontrivial example, the anharmonic oscillator is solved and the energy eigenvalues are obtained within the perturbation theory using the asymptotic iteration method

[en] It has been analyzed the ¹⁶O + ²⁸Si system within the framework of the optical model for 10 energies from 29.0 to 45.0 MeV, by using microscopic folded potentials. All potentials describe the individual angular distributions very well at forward angles. However, they fail to describe the individual angular distributions over the whole angular range up to 180 deg. Nevertheless, it has been able to explain the experimental data by modifying the surface region of the microscopic real potentials by adding two surface potentials

[en] We investigate the simultaneous explanation of the ⁶He+¹²C elastic and inelastic scattering and ⁶He+¹²C→⁴He+¹⁴C transfer reaction observables at 18.0 MeV within the framework of the coupled-channels Born approximation. In obtaining the microscopic double folding potentials, two different nucleon densities deduced from the no-core shell model and few-body model calculations for the ⁶He have been used. Although a good agreement between theoretical results and experimental data has been obtained for elastic scattering and transfer reactions data, the theoretical results underestimate the magnitude of the inelastic-2⁺ state data. We present in this article that the deformation of the imaginary part of the optical potential is very important and it overcomes the magnitude problem for the inelastic data for this system

[en] We investigate the observables of the ⁶He+¹²C system by using coupled-channels Born approximation. We try to address the role of the transfer channels in explaining the reaction observables. We noticed the inclusion of the transfer channels does not have large effect. However, we present that deformation of the imaginary potential has an important effect in explaining the elastic, inelastic and transfer reaction data simultaneously for this system.

[en] In this study, we construct the deformed form of the relativistic Duffin-Kemmer-Petiau (DKP) oscillator including a term qr³. The DKP oscillator with a deformed term becomes the radial sextic oscillator in the non-relativistic limit. The DKP sextic oscillator problem is solved numerically within the framework of the asymptotic iteration method. We present the energy eigenvalues for the ground and excited states.

[en] It is possible to excite atomic nuclei electromagnetically and even separate proton or neutron from a sample which is exposed to gamma rays by a clinical linac. Thus, the determination of the elemental concentration of a sample by photo-activation analysis is a reasonable attempt since it is related to the detailed analysis of the photonuclear reaction of an intended element. In this study, in order to get the proof of principle for photo-activation a titanium dioxide and a 10 kurus Turkish coin samples are irradiated with high energy bremsstrahlung photons at the end-point energy of 18 MeV and their zinc and copper concentrations are determined by a precise measurement with a high purity germanium detector. (paper)

[en] The ¹⁶O + ²⁸Si reaction has been widely studied both experimentally and theoretically and has been claimed to show indications of chaotic scattering. In order to examine this claim and to address whether reaction models such as the optical one could explain the experimental data, we have analyzed the ¹⁶O + ²⁸Si system within the framework of the optical model for ten energies from 29.0 to 45.0 MeV, by using microscopic folded potentials, which are based on M3Y nucleon-nucleon, alpha-alpha effective interactions and a phenomenological shallow potential. All potentials describe the individual angular distributions very well at forward angles. However, they fail to describe the individual angular distributions over the whole angular range up to 180^o. Nevertheless, we have been able to explain the experimental data by modifying the surface region of the microscopic real potentials by adding two surface potentials. With these correction potentials, we have obtained very good agreement for the individual angular distributions over the whole angular range for the given energies as well as for the experimental data near the Coulomb barrier. The failure of these optical potentials in explaining the scattering observables of this reaction without corrections puts a question mark on the model and supports the idea of a chaotic behavior

[en] We discuss medium corrections of the nucleon-nucleon (NN) cross sections and their influence on direct reactions at intermediate energies ≳50 MeV/nucleon. The results obtained with free NN cross sections are compared with those obtained with a geometrical treatment of Pauli-blocking and Dirac-Bruecker methods. We show that medium corrections may lead to sizable modifications for collisions at intermediate energies and that they are more pronounced in reactions involving weakly bound nuclei.