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.

https://link.springer.com/content/pdf/10.1140/epja/s10050-021-00411-0.pdf

8B+27Al scattering at low energies

Experiments with A = 6–8 exotic beams in RIBRAS

Abstract The dynamics of a nuclear open quantum system could be revealed in the correlations between the breakup fragments of halo nuclei. The breakup mechanism of a proton halo nuclear system is of particular interest as the Coulomb polarization may play an important role, which, however, remains an open question. Here we use a highly efficient silicon detector array and measure the correlations between the breakup fragments of 8 B incident on 120 Sn at near-barrier energies. The energy and angular correlations can be explained by a fully quantum mechanical method based on the state-of-the-art continuum discretized coupled channel calculations. The results indicate that, compared to the neutron halo nucleus 6 He, 8 B presents distinctive reaction dynamics: the dominance of the elastic breakup. This breakup occurs mainly via the short-lived continuum states, almost exhausts the 7 Be yield, indicating the effect of Coulomb polarization on the proton halo state. The correlation information reveals that the prompt breakup mechanism dominates, occurring predominantly on the outgoing trajectory. We also show that, as a large environment, the continuum of 8 B breakup may not significantly influence elastic scattering and complete fusion. 

/pdf/breakup-of-the-proton-halo-nucleus-8b-near-barrier-energies-31j3m1ze.pdf

Breakup of the proton halo nucleus 8B near barrier energies

An optical model analysis of the available data for A = 8 (
 $$^8$$
 He, $$^8$$
 Li and $$^8$$
 B) projectiles on different targets with light, medium and heavy mass has been performed. A systematic potential set based on a Woods–Saxon Potential shape was obtained. This potential describes the elastic scattering angular distributions quite well. A more physical model within the framework of a semi-microscopic approach, where the nuclear matter density distributions of the $$^8$$
 B, $$^8$$
 Li and $$^8$$
 He projectiles have been calculated by using a microscopic self-consistent relativistic mean field (RMF) theory, was also considered. The agreement of the calculated angular distributions with the data was reasonable. An improvement of the agreement could be achieved by changing the imaginary diffuseness parameter, which is a sensitive parameter in these calculations.

https://link.springer.com/content/pdf/10.1140/epja/s10050-021-00405-y

8B+27Al scattering at low energies

Citations

Experiments with A = 6–8 exotic beams in RIBRAS

Breakup of the proton halo nucleus 8B near barrier energies

Towards a systematic optical model potential for A = 8 projectiles