Li-α CLUSTER STATES IN 12B USING 8Li + 4He INVERSE KINEMATICS ELASTIC SCATTERING

Abstract

The 8Li elastic scattering on a 4He gas target was studied by means of the Inverse Kinematic Thick Target scattering method (TTIK) in order to investigate cluster configurations in excited states of 12 B . A 8 Li beam, at Ec.m. = 10.2 MeV , was provided by the EXCYT radioactive beam facility at Catania. The beam, while passing through the helium thick target decreases its energy, thus exploring the 8 Li -α center-of-mass energy range 2.7 MeV ≤ECM ≤9.6 MeV . Four Δ E - E silicon detector telescopes were used to detect the recoiling alpha particles. The time interval between the 8 Li passing through a micro-channel plate foil, placed at the entrance of the chamber, and the detection of the α particles by the Δ E detectors was also measured. The time measurement allows to disentangle elastic from reactions events, otherwise impossible from energy measurements. This can be considered as an improvement of the TTIK method. In this paper the used experimental technique and the obtained preliminary results will be presented.