Two-neutron transfer in Be7+Be9 collisions

Abstract

Elastic scattering and transfer cross sections for the 7 Be + 9 Be system have been measured at E lab = 23.1 MeV using the 7 Be radioactive secondary beam produced at Radioactive Ion Beams in Brazil facility at the University of São Paulo. The elastic scattering has been measured by detecting the 7 Be scattered at forward angles in the laboratory system. The transfer reaction 9 Be( 7 Be, 9 Be) 7 Be was identified by detecting the 9 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 Be(1/2−; 429 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 Be(p, t ) 7 Be data to check the consistency of our results results for the ( 7 Be, 9 Be) transfer reaction.

Investigation of the reaction mechanisms for B10+Au197 at near-barrier energies

“…The range of kinetic energy of the detected nuclei indicates that they can be produced in different processes: transfer 10 B + 197 Au → 9 Be + 198 Hg, and breakup 10 B + 197 Au → 9 Be + 197 Au + proton. Possibly, the 9 Be nuclei can also breakup in 9 Be → neutron + 8 Be, where the 8 Be breaks again in two α's. In fact, we have detected α particles in our spectra.…”

“…More recently, experiments aiming to investigate the role of cluster-transfer reactions have been performed with radioactive beams in inverse kinematics. The results have demonstrated that cluster-transfer reactions can be well described as a direct process, and thus they are an important tool to investigate the structure of radioactive neutron-rich nuclei [7][8][9]. However, the reaction mechanisms of systems involving light unstable weakly bound nuclei, such as 6,8 He or 11 Be, and stable weakly bound projectiles, such as 6,7 Li and 9 Be, can be extremely puzzling [10][11][12][13][14][15].…”

Evidence of the effect of strong stripping channels on the dynamics of the Li8+Ni58 reaction

“…III A and keeping the double-folding potential with scaling factors N r = 1 and N i = 0.6. A reduction in the strength of the bare imaginary potential with respect to the optical model potential is expected since the couplings to the transfer channels are explicitly taken into account [63,64]. The same scaling factors were assumed for the transition potentials between the 8 Li states.…”

An overview of the scientific contribution of Andrea Vitturi to nuclear physics

“…In Fig. 15 the effect of the interference of the elastic scattering and elastic transfer amplitudes is shown for the [115] and 9 Be( 7 Be, 9 Be) 7 Be [116], and the alpha transfer reaction 16 O( 12 C, 16 O) 12 C [117].…”