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To measure the total neutron cross sections, the authors developed a convenient technique using silicon semiconductor detectors with the simple and compact detecting system. The created technique was used to measure A + n total cross sections at the energy En = 14.1 MeV for several nuclei in different mass region. The neutron generator NG-150 in D + T regime of neutrons generation is used as fast neutrons source. The results of measurements and their comparison with the appropriate literature values are also presented.

The Geant4 code is used for Monte Carlo modeling of the angular distribution of the neutron yield from an 3H(d, n)4He reaction in a tritium target, and the effect the collimator unit has on the neutron flux. The number of all nuclear reaction channels in a 232Th + natU (50/50%) target per 14.1-MeV neutron is also found, along with the optimum size of the target for the maximum yield of secondary neutrons.

The activation method is proposed for collection of the sufficient statistics during the investigation of the nuclear astrophysical reactions at low energies with the short-living residual nuclei formation. The main feature is a multiple cyclical irradiation of a target by an ion beam and measurement of the radioactivity decay curve. The method was tested by the yield measurement of the 12 C( p ,γ) 13 N reaction with detecting the annihilation γγ- coincidences from 13 N(β + ν) 13 C decay at the two-arm scintillation spectrometer.

Double differential cross sections of the reaction 24Mg(p, pγ1.369)24Mg at Ep = 7.4 MeV are measured for proton emission angles of 30°–160° (lab.). All odd components of the density matrix spin-tensors of the 24Mg nucleus in the 2+ (1.369 MeV) state are restored and all its orientation characteristics are determined. The experimental results are compared to calculation results using the coupled channel method and assuming of the formation of resonance in the 25Al compound nucleus.

The original version of the activation method is presented and yield of the astrophysical relevant reaction [Formula: see text] has been measured at the energy region 190–650[Formula: see text]keV using this method. The rate of this reaction was calculated within the temperature region [Formula: see text] through the yield values. The possibility of improving the method for measuring very small yields or cross sections was demonstrated.

The proton transfer $^{7}\mathrm{Be}(d,n)^{8}\mathrm{B}$ reaction at the energy of 4.5 MeV (center of mass) has been analyzed within the modified distorted-wave Born approximation. New estimates and their uncertainties are obtained for values of the asymptotic normalization coefficients for $p+^{7}\mathrm{Be}\ensuremath{\rightarrow}^{8}\mathrm{B}$, the astrophysical ${S}_{17}(0)$ factor, and the $s$-wave $p+^{7}\mathrm{Be}$ scattering lengths.

The scattering process on 1p-shell nuclei, having the cluster structure, can be seen in the anomaly increasing of cross sections for large angles. Most often, this increasing of cross sections is connected with mechanism of transfer of clusters or nucleons. The study of the α-cluster transfer mechanism in the elastic scattering of 20Ne ions on 16O nuclei is important for investigation burning process in evolution of the Universe immediately after the Big-Bang. Therefore new experiment on the heavy ion accelerator (Warsaw University) was carried out with a significant expansion of the range of angles up to 1700 in center mass system at E Lab =50.0 MeV. Data analysis of angular distribution was performed in framework of the optical model and coupled channel method. The optimal parameters of the optical potential were obtained and the spectroscopic factor was obtained 1 for 20Ne as α +16O.

The elastic scattering of the 20Ne+16O system has been analyzed with a phenomenological potential approach within the framework of the optical and coupled-channels models at ELab =50.0 MeV. The striking feature of the experimental data is the oscillatory structure at the intermediate angles and a rapid increase at large angles. Optical potentials have difficulty in describing such structures and predict a fall of experimental data around the intermediate angles. In order to explain this structure, we have used a deep real potential with a sum of Woods-Saxon typed surface and volume imaginary potentials. We present that deep real potential with these imaginary potentials explain the oscillatory structure and backward rise observed in the elastic scattering data within both models. It should be pointed out that there is a magnitude problem of the inelastic 2+ data for the deformed 20Ne nucleus that the standard coupled-channels model is unable to predict correctly.