QUASI-FREE PROCESSES IN THE LI-6 BREAKUP REACTIONS BY ALPHA-PARTICLES

The differential cross sections for the Li-6(alpha, 2 alpha)H-2 and th e Li-6(alpha,(HeHe)-He-3-He-5)H-2 reactions have been measured at the bombarding energy of 118.4 MeV. For both reactions, enhanced quasifree peaks were observed. The angular dependences of the two-body cross se ctions, deduced from the three-body cross sections by using DWIA, were compared with the free cross sections. For the Li-6(alpha, 2 alpha)H- 2 reaction, the angular dependence for the quasifree scattering was si milar to that for the free elastic scattering and the absolute cross s ections were explained with a reasonable alpha d cluster probability i n Li-6. So the quasifree scattering process seems consistent with the free scattering. For the Li-6(alpha,(HeHe)-He-3-He-5)H-2 reaction, the angular dependence for the quasifree reaction process agreed with tha t for the free reaction; however, the absolute cross sections were abo ut twice as large as those for the free reactions, This might be due t o three-body structure effects in Li-6.