Study of reactions induced by the halo nucleus 11Li with the active target MAYA

10h30 - GANIL guest house 

Active targets are perfect tools for the study of nuclear reactions induced by very low intensity radioactive ion beams. They also enable the simultaneous study of direct and compound nuclear reactions. The active target MAYA, built at GANIL has been used to study the reactions induced by a 4.3A MeV ¹¹Li beam at the ISAC2 accelerator, TRIUMF (Canada). The angular distributions for the elastic scattering and the one and two neutron transfer reactions have been reconstructed. The elastic scattering angular distribution indicates a strong enhancement of the flux absorption with respect to the neighbouring nuclei. From a coupled channel analysis of the two neutron transfer reaction for different three body models, the informations on the structure of the halo of the borromean nucleus ¹¹Li have been extracted. Meanwhile, the energy dependence of the elastic scattering reaction has been studied, using the active target MAYA as a thick target. The resulting spectrum shows a resonance around 3 MeV centre of mass. This resonance could be an isobaric analog state of ¹²Li, observed in ¹²Be. R matrix calculations have been performed in order to extract the parameters (spin and parity) of this state.