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New experimental data for differential cross-sections of the 14C( 11B, 12C) 13B reaction obtained recently at the energy Еlab( 11B) = 45 MeV for the ground states of 13B and 12C were analyzed within the coupled reaction channels (CRC) method that included the 11B + 14C elastic scattering channel as well as channels for one- and two-step transfers of nucleons in the coupling scheme. The necessary 11B + 14C Woods - Saxon (WS) optical potential parameters for the entrance reaction channel were obtained from 11B elastic scattering in the previous work, while those for 12C + 13B interaction were deduced from fitting the CRC calculations to the 14C( 11B, 12C) 13B reaction data. Needed spectroscopic amplitudes of transferred nucleons and clusters were calculated within the translational-invariant shell model. The data are well described by the direct transfer of a proton while contributions from two-step transfers were found to be negligible. The deduced 13B + 12C WS optical potential parameters are compared with those of the 10,11,12B + 12C nuclei interactions. The effect of isotopic differences in these interactions was observed. [ABSTRACT FROM AUTHOR]

Complete angular distributions including both forward and backward angles are reported for the 14C(11B,10B)15C reaction at Elab(11B)=45 MeV for the ground and excited states of 10B and 15C. The experimental data were analyzed within the coupled reaction channels method that included the 11B+14C elastic scattering channel as well as channels for one- and twostep transfers of nucleons in the coupling scheme. The necessary 11B+14C optical potential parameters were obtained from previous work, while those for 10B+15C were deduced from fitting the CRC reaction calculations to the 14C(11B,10B)15C reaction data. Needed spectroscopic amplitudes of transferred nucleons and clusters were calculated within the translationalinvariant shell model. The data are well described by neutron transfers, while contributions from two-step transfers were found to be negligible. Recently published global optical potentials for the elastic scattering of the 8;10;11B isotopes were tested as part of the analysis and found to satisfactorily describe this reaction data if the surface imaginary potentials were omitted for both the entrance and the exit channels, and the parameters for volume real and imaginary potentials were slightly modified. [ABSTRACT FROM AUTHOR]

Complete angular distributions including both forward and backward angles are reported for the reaction 13C(11B, 12C)12B at Elab(11B) = 45 MeV leading to the ground and excited states of 12C and 12B. This reaction explores the interplay of proton and neutron transfers as well of those for larger clusters. The experimental data were analyzed within the coupled-reaction-channels method (CRC) that included the 13C+11B elastic scattering channel as well as channels for one- and two-step transfers of nucleons in the coupling scheme. The necessary 13C+11B optical potential parameters were obtained from previous work, while those for 12C + 12B were deduced from fitting the calculations to the 13C(11B, 12C)12B reaction data. Needed spectroscopic amplitudes of transferred nucleons and clusters were calculated within the translational-invariant shell model (TISM). The data are well-described by proton transfers while contributions from neutron transfer are only important at the largest angles. New global optical potentials for the elastic scattering of 8,10,11B isotopes were tested and found to describe the forward angles reaction data but not those for the middle and larger angles even when the ground-state reorientation of 11B in the entrance channel is included. [ABSTRACT FROM AUTHOR]

New experimental data for differential cross sections of the 14C(11B, 9Be)16N reaction were measured for the ground states of 9Be and 16N nuclei as well as for the excited states of 16N at the energy Elab.(11B) = 45 MeV. The reaction data were analyzed within the coupled-reaction channels method (CRC) for one- and two-step transfers of nucleons and clusters. In the CRC-calculations, the optical potential deduced from the analysis of the 11B + 14C elastic scattering data was used for the entrance reaction channel. Needed spectroscopic amplitudes of nucleons and clusters in nuclei were calculated within shell-model. 9Be + 16N optical potential parameters were deduced by fitting CRC cross-sections to the 14C(11B, 9Be)16N reaction data. Contributions of one- and two-step transfers of nucleons and clusters into the 14C(11B, 9Be)16N reaction cross-sections were obtained. [ABSTRACT FROM AUTHOR]

Angular distributions of the 7Li + 12C elastic and inelastic scattering as well as the 7Li(14N, X) reactions with exited stable and unstable nuclei with Z = 3-6 were measured at Elab(12C) = 115 MeV. The data were analyzed within the optical model and coupled-reaction-channels method. The elastic and inelastic scattering, reorientations of 7Li in ground and excited states as well as more important transfer reactions were included in the channels-coupling-scheme. 7Li + + 12C optical potential parameters for ground and excited states of 7Li and 12C as well as deformation parameters of these nuclei were deduced. The contributions of one- and two-step transfers in the 7Li + 12C elastic and inelastic scattering channels were estimated. [ABSTRACT FROM AUTHOR]

Angular distributions of the 6Li(18O, 17O)7Li reaction were measured at Elab(18O) = 114 MeV for ground and excited states of exit nuclei. The data were analyzed within the coupled-reaction-channels method (CRC). The 6Li + 18O elastic and inelastic scattering channels as well as the simplest one- and two-step reactions were included in the coupledreaction- channels scheme. In CRC calculations, the 6Li + 18O potential with parameters deduced from the elastic scattering data, was used for the entrance reaction channel. The spectroscopic amplitudes of nucleons and clusters were calculated within the translational-invariant shell model. The 7Li + 17O potential parameters were deduced by fitting 6Li(18O, 17O)7Li reaction data. Isotopic differences of the 7Li + 17O, 7Li + 18O and 7Li + 16O potential, as well as the reaction mechanisms are studied [ABSTRACT FROM AUTHOR]

Angular distributions of the 6Li + 18O elastic and inelastic scattering as well as the 6Li(18O, X) reactions with production of 16,17,19O + 8,7,5Li, 14,15,16,17N + 10,9,8,7Be and 12,13,14C + 12,11,10B nuclei were measured at Elab(18O) = 114 MeV. The data were analyzed within the optical model and coupled-reaction-channels method. The 6Li + 18O optical potential parameters as well as deformation parameters of these nuclei were deduced and the scattering mechanisms were studied. The isotopic differences between the 6, 7Li + 18O and 6Li + 16, 18O scattering as well as their potential parameters were investigated. [ABSTRACT FROM AUTHOR]

Angular distributions of the 7Li + 14N elastic and inelastic scattering as well as the 7Li(14N, X) reactions with production of 13, 15, 16N + 8, 6, 5Li, 11, 12, 13, 14C + 10, 9, 8, 7Be, 10, 11, 12B + 11, 10, 9B nuclei and others were measured at Elab (14N) = 80 MeV. The data were analyzed within the optical model and coupled-reaction-channels method. The elastic and inelastic scattering, reorientations of 7Li and 14N in ground and excited states as well as the prominent one- and two-step transfers were included in a channels-coupling-scheme. The 7Li + 14N optical potential parameters for ground and excited states of 7Li and 14N as well as deformation parameters of these nuclei were deduced. The contributions of oneand two-step transfers in the 7Li + 14N elastic and inelastic scattering channels were estimated. [ABSTRACT FROM AUTHOR]

New experimental data for differential cross sections of 14C(11B, 11B)14C inelastic scattering at the energy Elab.(11B) = 45 MeV for transitions of 11B nucleus to the excited states of 2,12 - 8,56 MeV were obtained. Experimental data were analyzed within optical model and coupled-reaction channels method. Elastic and inelastic scattering of nuclei, reorientation of spin of 11B and simplest transfers of nucleons and clusters were included in the coupling scheme. Woods - Saxon optical model parameters of 14C + 11B interaction and deformation parameters of 11B nucleus were deduced. Optical potential, deduced from the fit of experimental data, is compared to the respective foldingpotential, calculated by the method of double-folding. Isotopic differences of optical model potentials for 12,13,14C + 11B interaction, using the results of recent publications of 12,13C + 11B elastic and inelastic scattering at similar energies, were investigated. Contributions of one- and two-step transfers of nucleons and clusters into the elastic and inelastic channels of 14C + 11B scattering were defined. [ABSTRACT FROM AUTHOR]

The indirect method of the light exotic nuclei study in the experiments with the stable ion beams produced in many-nucleon-transfer reactions is presented. The data of elastic and inelastic scattering as well as of transfer reactions were analysed with the optical model (OM) and coupled-reactionchannels method (CRC). The potential parameters for the entrance reaction channel must be deduced from the analysis of the elastic and inelastic scattering data before the CRC-calculation of reaction cross-section. The results for the 12C(11B, 15N)8Be reaction are presented as an example. The energy dependence of optical potential parameters for this reaction are also presented. [ABSTRACT FROM AUTHOR]

Angular distributions of the 7Li + 10B elastic and inelastic scattering were measured at the energy E lab (10B) = 51 MeV (21 MeV c.m.). These and previously measured 7Li + 10B elastic-scattering data known at the 7Li-beam energies 24 MeV (14.1 MeV c.m.) and 39 MeV (22.94 MeV c.m.) were analyzed within the optical model and coupled-reaction channels method to determine the energy dependence of the parameters of the scattering potential and find the difference of these parameters from that of 7Li + 11B scattering. It was found that the 7Li + 11B potential parameters fail to describe the 7Li + 10B scattering data. The biggest difference is observed between the depths of the imaginary potentials that describe these scatterings. [ABSTRACT FROM AUTHOR]

Angular distributions of the12C(11B,15N)8Be reaction were measured at the energyElab(11 B) = 49 MeV for the transitions to the ground and 2.94 MeV (2+) excited state of8Be and to the ground and 5.270 MeV (5/2+) + 5.299 MeV (1/2+), 6.324 MeV (3/2-), 7.155 MeV (5/2+) + 7.301 MeV (3/2+), 7.567 MeV (7/2+) excited states of15N. The data were analyzed by the coupled-reaction-channel method. The elastic, inelastic scattering and one- and two-step transfers were included in the coupling scheme. The data of the12C(11B,8Be)15N reaction atEcm = 9.4-17.8 MeV known from the literature, were also included in the analysis. The mechanism of the12C(11B,15N)8Be reaction and the optical-model potential parameters for the15N +8Be channel were deduced. The energy dependence of the optical-model parameters for the15N +8Be channel was obtained. [ABSTRACT FROM AUTHOR]

Angular distributions of the 13C+11B elastic and inelastic scattering were measured for the first time at Elab(11B)=45 MeV in the full angular range for the transitions to the ground and excited states of the 11B and 13C nuclei. The data were analyzed within the optical model (OM) and coupled-reaction-channels (CRC) method. The mechanism of the 13C+11B anomalous large angle scattering (ALAS) was studied. The isotopic effects in the elastic and inelastic scattering of 13C+11B and 12C+11B are discussed. The OM potential parameters for the 13C+11B elastic scattering and deformation parameters of 11B and 13C were deduced. [Copyright &y& Elsevier]

The transfer reaction 13C(11B,7Li)17O leading to the ground and several excited states of 17O was investigated at an incident boron beam energy of 45 MeV. The experimental data were analyzed by means of coupled-channel Born approximation calculations and 17O=α+13C spectroscopic factors were extracted from a comparison of the data and the calculations at forward angles. The largest spectroscopic factor obtained was that for the subthreshold 6.356 MeV 1/2+ state, important for the production of neutrons in the stellar environment, and the squared Coulomb modified asymptotic normalization coefficient, C², is consistent with previous determinations. A significant rise in the experimental data at backward scattering angles suggested the possibility of 17O=6Li+11B clustering in some 17O states, including the ground state. However, explicit inclusion of 6Li transfer in the calculations could not explain the observed effect. Compound nucleus calculations suggested that while the backward angle rise could be explained by such processes for two of the populated 17O states other multistep direct processes must contribute significantly to the other two. [ABSTRACT FROM AUTHOR]

New angular distributions for the 7Li(18O,17N)8Be reaction at an energy of Elab(18O)=114 MeV for the ground states of 8Be and 17N and the excited states of 17N were measured. These data and 18O(d,3He)17N reaction data taken at Ed=52 MeV were analyzed within the coupled-reaction-channels method using 7Li+18O and 18O+d optical potentials deduced from previous elastic and inelastic scattering results. Shell-model spectroscopic amplitudes were used in the analysis. Both reactions are dominated by single proton transfer. Calculations show that heavy-ion reactions of the type studied in this work can be used to identify final-state spins when measurements are carried to small angles. [ABSTRACT FROM AUTHOR]

Angular distributions of the 9Be+11B elastic and inelastic scattering were measured at Elab(11B)=45 MeV in a large angular range for the transitions to the ground and excited states of the 11B and 9Be nuclei. The data were analyzed within the coupled-reaction-channels (CRC) method. We have also included the data of the 11B+9Be elastic scattering at Ecm≈9–22 MeV known from the literature. The mechanisms of the 9Be+11B anomalous large angle scattering (ALAS) were studied both for the elastic and inelastic channels including the 9Be and 11B reorientations and transfer reactions. The optical potential parameters for the 9Be+11B elastic scattering and the 11B and 9Be deformation parameters were deduced. [Copyright &y& Elsevier]