Sequential reactions induced by alpha particles on 3He

A prominent peak is observed in the forward-angle spectra of α particles if ³He is bombarded by 63.7-, 71.7-, or 81.4-MeV α particles. The energy of the peak is consistent with a sequential decay process involving the 2.18-MeV state of ⁶Li. At 71.7 MeV, proton spectra measured at backward angles show that the cross sections for formation of ⁶Li* (2.18 MeV) agree with the intensity of the prominent α peak. The peak shape and position imply that the α particles are preferentially emitted forward with respect to the original ⁶Li* direction. Two other peaks are observed in some of the α spectra, one of them possibly the result of a sequential decay involving ⁵Li.[NUCLEAR REACTIONS ³He(α,α'), (α,p), E=63.7,71.7,81.4 MeV; measured σ(E,θ).]