abstract

A new form of potential is used to treat the optical model unequivocally for the analysis of scattering results of the \(\mathrm {^{58}Ni}+\mathrm {^{27}Al}\) system. The phenomenological optical potential is formed with the Ginocchio potential for analysis near the Coulomb barrier. Theoretical calculations explain the experimental outcomes over a wide range of colliding energies, and hence exhibit threshold anomaly. An inbuilt non-trivial behaviour in the formulation near the Coulomb barrier position is found essential for a successful explanation of the experimental results.

abstract

The most precise measurement of the CP asymmetry in the \(B^-\rightarrow D_s^-D^0\) decay has been reported by the LHCb Collaboration with the value of \((-0.4\pm 0.5\pm 0.5)\%\). In this study, the CP violation in the \(B^-\rightarrow D_s^-D^0\) decay has been calculated under the factorization approach. This decay mode includes the current–current tree, and penguin diagrams and their amplitudes are considered separately. In each of the tree and penguin amplitudes, the strong and weak phases have been introduced. The CP asymmetry has been calculated in this work to be \((-0.35\pm 0.03)\%\). Finally, from the sum of the amplitudes, we have calculated the total amplitude and obtained comparable results with the experimental value for the branching ratio of \(B^-\rightarrow D_s^-D^0\) decay.

abstract

We have performed calculations to study the ground-state properties, i.e. , the binding energy per nucleon and two-proton separation energy of Fe, Ni, Zn, Ge, Kr, and Zr isotopes by using the relativistic mean-field (RMF) approach with the force parameter NL3*. The obtained results are in excellent agreement with the available experimental data. We have also performed systematic studies of the two-proton (\(2p\)) radioactivity, the two-proton decay energy (\(Q_{2p}\)) using the RMF (NL3*) approach, the finite-range droplet model (FRDM), and the Weizsacker–Skyrme-4 (WS4). Then, the effective liquid drop model (ELDM) is applied to find out the two-proton decay half-lives using three kinds of evaluated \(Q_{2p}\) values. The two-proton decay half-lives calculations are also carried out by using empirical formulas, namely Liu and Sreeja, and their comparisons with ELDM results are found to be in agreement. Also, we predict the half-lives of possible nuclei of the two-proton radioactivity in the range of \(30 \leq Z \leq 40\) with released energy \(Q_{2p} \gt 0\) obtained by the RMF (NL3*) model. The estimated results reveal a clear linear connection between the logarithmic two-proton decay half-lives \( \log _{10}T_{1/2} \) and Coulomb parameters [(\(Z_d^{0.8}+l^{0.25}\)) \(Q_{2p}^{-1/2}\)].

abstract

In this work, we investigate the mass spectrum of \(1^{1}D_{2}\) and \(1^{3}D_{2}\) meson nonets in the framework of the meson mass matrix and Regge phenomenology. The results are compared with the values from different phenomenological models and may be useful for the assignment of the \(1^{1}D_{2}\) and \(1^{3}D_{2}\) meson nonets in the future.

abstract

In this study, we tried to evaluate the quadrupole transition rates and moments of the \(\mathrm {^{104-110}Pd}\) isotopic chain and report on the structural changes of these nuclei based on the variation of the transition probabilities. To this aim, the electric quadrupole transition probabilities of considered nuclei are calculated in both interacting boson models 1 and 2 frameworks. Different levels are labelled and described by the quantum numbers of affine SU(1,1) infinite-dimensional algebra between U(5) and O(6) dynamical limits of considered models. The relation of calculation accuracy and the effective charges in comparison with quadrupole deformation and experimental half-lives are considered. The interacting boson model 1 makes more exact results for the only intra-band quadrupole transition rates and also such Pd isotopes which have the lowest quadrupole deformations. Similarly, the interacting boson model 2 makes more exact predictions for inter-band transitions and also such transitions originated from the intruder state. There are some significant changes in the quadrupole moments of different levels in such nuclei which suggested them as candidates for the E(5) critical point.