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The influence of the tensor interaction of nucleons on the characteristics of neutron-rich silicon and nickel isotopes was studied in this work. Tensor forces are taken into account within the framework of the Hartree-Fock approach with the Skyrme interaction. It is shown that the addition of tensor component of interaction improves the description of the splitting between different single-particle states and leads to a decrease in nucleon-nucleon pairing correlations in silicon and nickel nuclei. Special attention was given to the role of isovector tensor forces relevant for interaction of like nucleons., Comment: 13 pages, 7 figures, accepted in Chinese Physics C

A study of the inelastic scattering of neutrons with an energy of $14.1$~MeV on the nuclei of oxygen, phosphorus and sulfur was carried out at the TANGRA facility at JINR (Dubna). The purpose of the experiment was to refine existing and obtain new data on the yields and angular distributions of $\gamma$-quanta emitted by the studied nuclei as a result of neutron-induced nuclear reactions using the tagged neutron method. Two types of detector systems were used to register $\gamma$-quanta. The $\gamma$-ray yields were measured using a high-purity germanium (HPGe) detector. The angular distributions of $\gamma$-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi$_{4}$Ge$_{3}$O$_{12}$ (BGO) located around the sample. As a result of the studies carried out, the yields of two transitions for the reaction of tagged neutrons with $^{16}$O, nine transitions for the reaction with $^{31}$P, and nine transitions for the reaction with $^{32}$S were measured for the first time. The angular anisotropy of the $\gamma$-radiation accompanying the inelastic scattering of neutrons with an energy of $14.1$~MeV on $^{31}$P nuclei was also measured for the first time., Comment: 16 pages, 11 figures. Accepted for publication in Chinese Physics C

Various estimates of the even-odd effect of the mass shell of atomic nuclei are considered. Based on the experimental mass values of the Ca, Sn, and Pb isotopes, the dependence of the energy gap on the neutrons number is traced and the relationship of this characteristic to the properties of external neutron subshells is shown. In nuclei with closed proton shells, effects directly related to neutron pairing and effects of nucleon shells are discussed., Comment: corrected typos

The ground state multiplet structure for nuclei over the wide range of mass number $A$ was calculated in $\delta$-approximation and different mass relations for pairing energy was analysed in this work. Correlation between the calculated multiplet structure and experimental data offer a guideline in deciding between mass relations for nucleon pairing., Comment: 6 pages, 2 fig., Proceedings of Intern. Session-Conference of the Section of Nuclear Physics of PSD RAS (April 12 - 15, 2016, JINR Dubna), to be published in Journal Physics of Elementary Particles and Atomic Nuclei (PEPAN)

We discuss the experimental data on the n,e-scattering length bne and the values of mean square charge radius of the neutron obtained from them. It is shown that the accumulated during the last 50 years most significant experimental estimates of the bne are not contradictory and lead to the average value =-0.1178+-0.0037 fm^2. Assuming that all the authors have underestimated the errors of their measurements by a factor of 1.7, the combined fit of all available experimental data would lead to Chi^2~1 per degree of freedom. Different modern theoretical predictions of are considered. They are found to be in a good agreement with the obtained experimental value . However the existing theoretical description of the structure of neutron does not provide a value of with a sufficient accuracy., Comment: 8 pages, 1 figure