International Journal of Modern Physics E

The 2017 update of the discovery of nuclide project is presented. 34 new nuclides were observed for the first time in 2017. However, the assignment of six previously identified nuclides had to be retracted.

Cross sections of reaction products were measured in ${}^{28}$Si${+}^{93}$Nb reaction using recoil catcher technique involving by off-line gamma-ray spectrometry at beam energies of 105 and 155MeV. At $E_{\mathrm{\text{lab}}}=155$MeV, the contribution from different incomplete mass transfer processes is investigated. Results of the present studies show the contribution from deep inelastic collision (DIC), massive transfer or incomplete fusion (ICF) and quasi-elastic transfer (QET). The contribution from massive transfer reactions was confirmed from the fractional yield of the reaction products in the forward catcher foil. The present results are different from those from the reactions with comparatively higher entrance channel mass asymmetry with lighter projectiles, for which dominant transfer processes are ICF and QET which involve mass transfer predominantly from projectile to target. The $N/Z$ values of the products close to the target mass were observed to be in a wide range, starting from $N/Z$ of the target (${}^{93}$Nb) and extending slightly below the $N/Z$ of the composite system, consistent with the contribution from DIC and QET reactions. At $E_{\mathrm{\text{lab}}}=105$MeV, a small contribution from QET was observed in addition to complete fusion.

In this work, we calculate the neutron anomalous magnetic moment (AMM) supposing that this value can depend on the density and magnetic field of the system. We employ the lowest-order constraint variation (LOCV) method and $A{V}_{18}$ nuclear potential to calculate the medium dependency of the neutron AMM. It is confirmed that the neutron AMM increases by increasing the density, while it decreases as the magnetic field grows. The energy and equation of state for the system have also been investigated.

In the framework of relativistic mean-field theory, the ground state properties like binding energy, charge radius and quadrupole deformation parameter for various isotopes of zirconium from the valley of stability to drip-line region have been studied. The results are compared with the experimental data and we found reasonable agreement. The calculations are carried out for $\beta$-decay energy and $\beta$-decay half-life up to the drip-line. Total reaction and elastic differential cross-sections are also studied for few zirconium isotopes as projectiles with ${}^{12}\mathrm{\text{C}}$ as target, using different parameter sets namely NL3*, DD-ME2 and DD-PC1 in conjunction with Glauber model.

The consequences of some symmetries of the three-alpha system are discussed. In particular, the recent description of the low-energy spectrum of the ${}^{12}$C nucleus in terms of the algebraic cluster model (ACM) is compared to that of the multichannel dynamical symmetry (MUSY), which is the intersection of the shell and cluster models. The previous one applies interactions of a $D_{3h}$ geometric symmetry [D. J. Marin-Lambarri et al., Phys. Rev. Lett. 113 (2014) 012502], while the latter one has a U(3) dynamical symmetry. The available data is in line with both descriptions.

The $\beta$-delayed particle emission from the exotic nucleus ${}^{23}$Si has been studied using a detection system with silicon array and clover-type high-purity germanium (HPGe) detectors. The $\beta$-delayed charged-particle spectrum and $\gamma$-ray spectrum were identified. The half-life of ${}^{23}$Si has been determined. A new $\beta$-delayed proton branch with an energy of 3811keV was observed. The $\beta$-delayed two-proton emission was confirmed.

We formalized the nuclear mass problem in the inverse problem framework. This approach allows us to infer the underlying model parameters from experimental observation, rather than to predict the observations from the model parameters. The inverse problem was formulated for the numerically generalized semi-empirical mass formula of Bethe and von Weizsäcker. It was solved in a step-by-step way based on the AME2012 nuclear database. The established parametrization describes the measured nuclear masses of 2564 isotopes with a maximum deviation less than 2.6MeV, starting from the number of protons and number of neutrons equal to 1.

The explicit form of unknown functions in the generalized mass formula was discovered in a step-by-step way using the modified least ${\chi }^2$ procedure, that realized in the algorithms which were developed by Lubomir Aleksandrov to solve the nonlinear systems of equations via the Gauss–Newton method, lets us to choose the better one between two functions with same ${\chi }^2$. In the obtained generalized model, the corrections to the binding energy depend on nine proton (2, 8, 14, 20, 28, 50, 82, 108, 124) and ten neutron (2, 8, 14, 20, 28, 50, 82, 124, 152, 202) magic numbers as well on the asymptotic boundaries of their influence. The obtained results were compared with the predictions of other models.

By changing the neutron and nuclear matter incompressibility constant $K$, we investigate the isotopic behavior of the fusion barriers for the collision of large number of different isotopes with condition of $0.7\le N/Z\le 1.36$. Here, the double folding (DF) model which is accompanied by density-dependent (DD) versions of M3Y interactions is adopted as a basic heavy ion–ion potential. We show that the selected DD potentials predict a linear behavior for the calculated fusion barrier heights as a function of $(N/Z-1)$ for both proton- and neutron-rich systems. Moreover, the results indicate that the isotopic behavior of these values depend linearly on the change in the $K$ constant. The isotopic studies conducted on the fusion cross-section also shows that the properties of the nuclear matter in the range of energy which is below the fusion barrier will quite affect the fusion process.

Direct method for detecting intranuclear clusters of nuclear matter-clusters and determining their effective numbers was developed. The idea of the method is based on the functional coincidence of kinematics for light nuclei in the free state and clusters of the same mass within the nuclear volume. The reliability of the method is additionally confirmed by two experimental methods. The experiments were carried out at the Kazakhstan U-150M accelerator on a beam of $\alpha$-particles with energy of 29MeV. The first method consists in measuring the half-width of the elastic scattering peak from the angle and a comparison between the differential cross-sections of elastically scattered $\alpha$ particles on free light nuclei and the differential cross-sections obtained by the authors on intranuclear multicluster. Using the second method, the correlation method, an experiment was performed to record the scattered $\alpha$ particle on the ⁹Be nucleus-matrix and the recoil nucleus identical to it ($\alpha$ particle). Thus, the kinematics of the ${}^4\mathrm{\text{He}}(\alpha ,\alpha )$ ⁴He reaction, where ⁴He is an intranuclear $\alpha$ cluster, indicates the presence of an intranuclear alpha cluster, which is further confirmed by the authors, an experimental measurement of intranuclear multicluster.