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The $^{8}\mathrm{Li}+^{58}\mathrm{Ni}$ collision is investigated at 23.9, 26.1, 28.7, and 30 MeV bombarding energies. Quasielastic angular distributions and the singles $^{7}\mathrm{Li}$ angular and energy distributions are presented. Coupled-reaction channels (CRC) calculations, which include the coupling of the elastic channel to $^{59}\mathrm{Ni}=^{58}\mathrm{Ni}\phantom{\rule{0.16em}{0ex}}+\phantom{\rule{0.16em}{0ex}}n$ states above and below the neutron threshold, provide a simultaneous description of the quasielastic and transfer distributions and evidence the strong effect of the one-neutron transfer/breakup channels on the quasielastic scattering. The $^{7}\mathrm{Li}$ angular and energy distributions have been also successfully analyzed combining the continuum discretized coupled channels (CDCC) method, for the elastic breakup, and the IAV model of Ichimura, Austern, and Vincent [Phys. Rev. C 32, 431 (1985)], for the nonelastic breakup. These calculations indicate that most of the $^{7}\mathrm{Li}$ yields are due to nonelastic breakup contributions (transfer), whereas elastic breakup plays a minor role.

A feasibility study of two-neutron transfer reactions, using 12C and 19F targets, was performed. In this experiment, a 6He beam at 20 MeV incident energy was delivered by the RIBRAS facility. The main goal of this work was to test the RIBRAS system, operated in a single-solenoid mode, to investigate (6He,α) reactions in light nuclei. The excitation function of the 14C nucleus, populated by the 12C(6He,α) reaction, was extracted from the data. Evidence of nn-transfer reactions populating the ground state and the first 0 1 + state in 14C were observed. However, the present spectrum might have contribution from other reaction channels such as the 6He breakup. Future experiments with the RIBRAS dual-solenoid mode will improve the quality of the data by reducing a significant amount of background.

Experiments with secondary radioactive beams $$^6$$ He, $$^7$$ Be, $$^8$$ Li and $$^8$$ B on several targets have been performed in recent years at the Radioactive Ion Beams facility in Brasil (RIBRAS). We present results of elastic scattering and reaction measurements performed with this facility. A preliminary Coulomb excitation experiment using gamma-particle coincidence technique is described.

In this contribution, we report on effects due to the cluster configuration of boron isotopes, \(^8\)B, \(^{10}\)B, \(^{11}\)B and \(^{12}\)B, in the elastic scattering on \(^{58}\)Ni target at energies close to the Coulomb barrier. The results of coupled channel calculations, where the different configurations of the boron isotopes, \(^8\)B \(=\) \(^7\)Be\(+\)p, \(^{10}\)B \(=\) \(^6\)Li\(+\) \(\alpha \), \(^{11}\)B \(=\) \(^7\)Li\(+\) \(\alpha \) and \(^{12}\)B \(=\) \(^{11}\)B\(+\)n, have been attributed to different effects in the angular distributions for the elastic scattering process, are present.

Alpha particle energy distributions in the 6He+120Sn collision have been measured at 7 bombarding energies above the Coulomb barrier. A phenomenological analysis of the centroids of the experimental distributions was performed and compared with the expected alpha-particle energies from breakup and neutron transfer reactions. Q-optimum conditions were determined using the Brinks formula for the di-neutron transfer reaction. A comparison of the measured alpha-particle production cross-sections with Continuum Discretized Coupled Channels (CDCC) calculations for breakup is presented. Fundacao de Amparo `a Pesquisa no Estado de Sao Paulo 2013/22100-7, 2014/19666-1 Conselho Nacional de Desenvolvimento Cientıfico e Tecnologico 308935/2018-7 Ministerio de Economía y Competitividad FIS2017-88410-P European Union 654002

Elastic scattering and transfer cross sections for the $^{7}\mathrm{Be}+^{9}\mathrm{Be}$ system have been measured at ${E}_{\mathrm{lab}}=23.1\phantom{\rule{0.28em}{0ex}}\mathrm{MeV}$ using the $^{7}\mathrm{Be}$ radioactive secondary beam produced at Radioactive Ion Beams in Brazil facility at the University of S\~ao Paulo. The elastic scattering has been measured by detecting the $^{7}\mathrm{Be}$ scattered at forward angles in the laboratory system. The transfer reaction $^{9}\mathrm{Be}(^{7}\mathrm{Be},^{9}\mathrm{Be})^{7}\mathrm{Be}$ was identified by detecting the $^{9}\mathrm{Be}$ scattered at the same laboratory angles. The elastic angular distribution has been analyzed by optical model calculations using a Woods-Saxon form factor whose parameters have been varied to best reproduce the experimental data at forward angles. Coupled reaction channels calculations (CRC) have been performed to describe the transfer, considering the coupling to the transfer channel and including contributions to the ground state and to the first excited state of $^{7}\mathrm{Be}(1/2\ensuremath{-};429\phantom{\rule{0.16em}{0ex}}\mathrm{keV}$) in the final state. The spectroscopic amplitudes used in the CRC calculation have been derived from shell-model calculations. Similar CRC calculations were applied to existing $^{9}\mathrm{Be}(p,t)^{7}\mathrm{Be}$ data to check the consistency of our results results for the ($^{7}\mathrm{Be},^{9}\mathrm{Be}$) transfer reaction.

Elastic scattering of a radioactive neutron-rich boron isotope, $^{12}\mathrm{B}$, has been measured for the first time. Angular distributions for the elastic scattering of $^{12}\mathrm{B}+^{58}\mathrm{Ni}$ have been measured at ${\mathit{E}}_{\mathrm{Lab}}=30.0$ and 33.0 MeV, which are just above the Coulomb barrier (${\mathit{V}}_{\mathrm{B}}=24$ MeV). The obtained angular distributions were analyzed in terms of the large-scale coupled channel (CC) and coupled reaction channel (CRC) calculations, where several inelastic transitions for the target, as well as the most relevant transfer reactions, have been included in the coupling matrix elements. The roles of the spin reorientation and spin-orbit interaction in the reaction mechanism were also investigated. The one-neutron transfer reaction through a coupled reaction calculation had some effect on the elastic scattering of the system studied.

An overview of the experiments performed at RIBRAS over the last year is presented. Elastic scattering and breakup reactions induced by light exotic projectiles on different targets have been measured and some results are presented here for the 120Sn(6He, α) reaction. Resonant scattering experiments have been performed with 10Be and 12C secondary beams on a CH2 thick target and the well known 12C+p resonance was identified. A gamma-particle experiment using a new system of LYSO scintillators to detect gammas was done.

In this work we present an elastic scattering angular distribution for the 8Li+58Ni system measured at Elab = 26.1 MeV. The 8Li beam was produced in the Radioactive Ion Beams in Brasil (RIBRAS) facility using the 7Li primary beam delivered by the 8-UD Pelletron accelerator. The angular distribution covers the angular range from 20 to 85 degrees in the center of mass frame. The data have been analysed by optical model and coupled channels calculations, including couplings to low-lying states in 8Li and the spin-orbit interaction. Our results indicate that the inclusion of the spin-orbit interaction in the calculations is important to describe the data at backward angles.