The 7He nucleus was studied using the 6He[Formula: see text]He reaction in inverse kinematics at 29 [Formula: see text]MeV 6He beam delivered by the ACCULINNA-2 fragment separator (FLNR, JINR). The registration of neutrons from [Formula: see text] decay made it possible to derive the 7He ground state parameters, the decay energy of 0.38(2)[Formula: see text]MeV and width of 0.11(3)[Formula: see text]MeV.

An experiment was conducted for studying the cluster structure of Be induced by He ions at an energy of 30 MeV. As results of the nuclear reaction 3He + 9Be, the differential cross sections for the exit channels – elastic, inelastic, α + 8Be, 6He + 6Be, 6Li + 6Li, and 7Be + 5He – were measured. Elastic and inelastic scattering data were treated within both the optical model and coupled channel method. A new set of optical potentials was considered for the elastic scattering. The deformation parameter was established for the transition . Cluster transfer reactions were analyzed via the coupled reaction channel method. The nuclear reactions with the exit channels 6He + 6Be, 6Li + 6Li, and 7Be + 5He were complemented by two-step transfer mechanisms. The contribution of each reaction mechanism were shown and compared with the findings of other authors.

The (7) He nucleus was studied by the ( d , p ) reaction at 29 A MeV beam energy. The He-7 spectrum was measured up to 8 MeV above the (6) He + n threshold. The forward-backward asymmetry in the neutron emission from unbound states of (7) He has been found. That implies the presence of a positive parity partial wave in the (7) He spectrum.

The three-body model α + n + p for 6Li is applied as a probe with elastic scattering of α -particles. Elastic scattering is described within the optical model framework, while the rising of the cross section at the backward scattering angles is treated by means of an approximation of the np transfer mechanism. Both parts of the optical potential are obtained by fitting the depths of the same folding potentials to experimental data. The folding potential, in turn, is based on the three body-wave function of 6Li. Spectroscopic amplitudes for the np cluster are extracted in calculations based on the CRC method. One-step and two-step transfer mechanisms are taken into account for the np transfer mechanism. The calculation results indicate the dominance of the one-step mechanism over the two-step transfer mechanism of the np cluster.

The elastic and inelastic scatterings of deuterons from [Formula: see text]C are registered in a wide range of angles at the laboratory energy of 14.5[Formula: see text]MeV. Data on the differential cross-sections are treated within both the optical model and coupled-channels method. A new set of optical potential parameters is found. Analyses of the [Formula: see text] nuclear reactions are carried out for the levels of excitation 3.089, 8.86 and 9.87[Formula: see text]MeV. The single particle [Formula: see text], and cluster [Formula: see text] models are applied in calculations of differential cross-sections. The calculations show that the state 3.089[Formula: see text]MeV is populated with the single particle configuration, while the latter bands 8.86[Formula: see text]MeV and 9.87[Formula: see text]MeV mainly have the cluster [Formula: see text] excitation. The major contribution of the Hoyle state of the core [Formula: see text] is not observed, but the cluster [Formula: see text] configuration is ascertained to be the main contributor to the state 8.86[Formula: see text]MeV.

A three-body model alpha + 2N for 6He is applied using the wave function obtained within the stochastic variational method based on the Gaussian basis. An explicit expression is obtained for the density distribution function of nuclear matter. The elastic scattering of 6He by alpha-particles is studied in detail. By employing the calculated density distribution functions, the folding interaction potentials are built. The resulting folding potential is applied to calculate the differential cross sections of elastic scattering in the framework of the optical model. In order to treat the excess experimental cross sections at the large angles, the mechanisms of two nucleon transfer are proposed. With the proposed theoretical approach, good agreement in the comparison of calculated differential cross sections with the experimental data is demonstrated. It is also shown that the two-step transfer mechanisms of two nucleons predominate over one-step transfer mechanisms.

Elastic-scattering processes in the ^3He+^9 Be reaction are studied on the basis of the 2 α+n three-body cluster model of the ^9 Be nucleus. The ^9 Be three-body wave function obtained by the variational method in the Gaussian basis is used to derive an analytic representation of nuclear-matter density distribution. The interaction potential calculated for the ^3He+^9 Be system by the double-folding method is employed to analyze experimental data on the differential cross section for the elastic-scattering process ^9 Be ( ^3 He, ^3 He) ^9 Be at collision energies between 30 and 60 MeV.

Elastic-scattering processes in the He-3 + Be-9 reaction are studied on the basis of the 2 alpha + n three-body cluster model of the Be-9 nucleus. The Be-9 three-body wave function obtained by the variational method in the Gaussian basis is used to derive an analytic representation of nuclear-matter density distribution. The interaction potential calculated for the He-3 + Be-9 system by the double-folding method is employed to analyze experimental data on the differential cross section for the elastic-scattering process Be-9 (He-3, He-3)Be-9 at collision energies between 30 and 60 MeV.

Angular distributions of protons, deuterons, tritons, and alpha particles emitted in the reaction 2H+9Be at Elab=19.5, 25, and 35 MeV were measured to study the structure of 9Be, especially to shed light on the internal clusters and possible cluster transfer of 5He. The experiments were performed at sufficiently high energies to ensure suppression of compound nucleus contribution. Thus, the direct reaction mechanism should be mainly responsible for the measured five-nucleon transfer cross section. The analysis suggests a significant contribution of simultaneous five-nucleon transfer in the reaction channel 9Be (d,4He) 7Li.

Matter distributions of light nuclei in the three body model [6He,6Li : (α + n + n) and9Be : (α + α + n)] is theoretically expressed. As a quantum state of the system was adopted a wave function based on the multi dynamic cluster model. Within the multi dynamical cluster model with Pauli projection, matter density distribution and matter rms radius for nuclei6He,6Li,9Be were analytically calculated. Comparisons of calculated matter radii with experimental data are presented.

A generalized optical potential for elastic scattering induced by light nuclei is calculated within the Feshbach projection operator method. The model explicitly takes into account the contribution of the projectile break-up continuum treated within a microscopic few-cluster model. In this work we formulate the model, deriving an explicit expression for the optical potential, and show ability of the model applying it to deuteron elastic scattering.

The three-body wave function built on the basis of the Gaussian function, calculated using the three-body Hamiltonian with the Pauli blocking operator is studied. As an example, the wave function of the ground state of the 9 Be was taken. Analytical expressions are presented for the overlap matrix elements of the basis function for both basic and alternative set of relative Jacobi coordinates. The correlation densities of the wave function are calculated and illustrated depending on the set of orbital quantum numbers.

The paper describes the NRV web knowledge base on low-energy nuclear physics developed in the Joint Institute for Nuclear Research. The NRV knowledge base working through the Internet integrates a large amount of digitized experimental data on the properties of nuclei and nuclear reaction cross sections with a wide range of computational programs for modeling of nuclear properties and nuclear dynamics. Today, the NRV becomes a powerful instrument for nuclear physics research as well as for educational applications. Advantages of the functioning scheme of the knowledge base provide the synergy of coexistence of the experimental data and computational codes within one platform.

The NRV web knowledge base on low-energy nuclear physics has been created in the Joint Institute for Nuclear Research. This knowledge base working through the Internet integrates a large amount of digitized experimental data on the properties of nuclei and nuclear reaction cross sections with a wide range of computational programs for modeling of nuclear properties and various processes of nuclear dynamics which run directly in the browser of a remote user. Today, the NRV knowledge base is a powerful instrument for nuclear physics research. The basic principles of the NRV knowledge base are covered, and a brief description of its structure is given. The practical usage of the NRV knowledge base for both scientific and educational applications is demonstrated in detail.

Angular distributions of protons, deuterons, tritons and alpha particles emitted in the d + Be-9 reaction at E-lab = 19.5 and 35.0 MeV have been measured. The elastic scattering channel is analysed in the framework of both the optical model and the coupled-channel approach. The interaction potential of the d + Be-9 system is calculated in the framework of the Double-Folding model using the alpha + alpha + n three-body wave function of the Be-9 nucleus. The (d, p) and (d, t) one-nucleon-transfer reactions are analysed within the coupled-reactionchannel approach. The spectroscopic amplitudes for the different nuclear cluster configurations are calculated. Differential cross sections for the reaction channel Be-9(d, alpha) Li-7 are calculated including all possible reaction mechanisms within the coupled-reaction-channel method. Corresponding contributions to the cross sections are analysed.

The NRV web knowledge base on low-energy nuclear physics has been created in the Joint Institute for Nuclear Research. This knowledge base working through the Internet integrates a large amount of digitized experimental data on the properties of nuclei and nuclear reaction cross sections with a wide range of computational programs for modeling of nuclear properties and various processes of nuclear dynamics which run directly in the browser of a remote user. Today, the NRV knowledge base is both a powerful tool for nuclear physics research and an educational resource. The system is widely used, as evidenced by the large number of user queries to its resources and the number of references to the knowledge base in the articles published in scientific journals. The practical usage of the NRV knowledge base for both scientific and educational applications is demonstrated.