Three-body final states of the 3He+ 7Li reaction and clustering in 7Li

Abstract

Absolute coincidence cross sections for five three-body final states of the 3He+ 7Li reaction have been measured with 37.5 MeV incident 3He ++ ions at geometries where quasi-elastic scattering could occur. The spectra were fitted with plane wave (PWIA) and/or modified plane wave impulse approximation (MPWIA) calculations. Data from the 7Li( 3He, 3He t)α reaction were consistent with strong α-t clustering in 7Li. The yield from the reaction 7Li( 3He, 3He d) 5He was equally large but inconsistent with the existence of deuteron clusters when interpreted by the MPWIA. Momentum distributions of spectator α and 5He particles from these reactions were consistent with l = 1 and l = 0, respectively. Cross sections for the 3He+ 6Li+n, 3He+ 6He+p and t+ 6Li+p final states were small, inconsistent with PWIA predictions for l = 1, and hence indicate very small 6Li and 6He cluster probabilities in 7Li.