Elastic Scattering of Vector Polarized 6Li

Using the vector polarized 6Li-beam of the Heidelberg EN-Tandem1) the elastic scattering of 6Li on 12C, 16O, 28Si and 58Ni has been investigated at a bombarding energy of ELi = 22.8 MeV. The structure of the observed angular distributions of σ/σR depends in heavy ion scattering critically on E/Ecoul. Therefore the observed angular distributions of σ/σR display for 12C (E/Ecoul≈ 3.5) an oscillating pattern (fig.1) which looks like Frauenhofer diffraction scattering. The angular distribution of σ/σR for 58Ni (E/Ecoul≈ 1.4) is without any structure (fig.1) and looks like Fresnel diffraction scattering. The analyzing power had been obtained by measuring successively with a polarized and unpolarized beam (high frequency transition of the source1) on and off respectively). The polarization of the beam is known to be between 0.52 and 0.6. The lower bound is deduced from the highest up to now with this source observed asymmetry in the 6Li-4He elastic scattering2). The higher bound is estimated from the source parameters itself1). The polarization was monitored after some couple of runs either with the 1H(6Li,4He)3He reaction or, in a later stage of the experiment using the elastic scattering of 6Li on 12C. Around θcm = 44.5° and ELi = 22.8 MeV a flat maximum of the asymmetry connected with a fairly high cross section had been observed (fig.1).