Quasifree scattering at low energies inLi6(α, 2α)H2

$\alpha -\alpha$ quasifree scattering was investigated in the reaction ${}_{}{}^6{}_{}{}^{}\mathrm{Li}(\alpha , 2\alpha ){}_{}{}^2{}_{}{}^{}\mathrm{H}$ as a function of energy of the incident $\alpha$ particles. In the energy range $E_{\alpha }=6.6\mathrm{} \mathrm{to} 13.0$ MeV 51 spectra under kinematically complete conditions were obtained at symmetrical angles such that the spectator momentum $p_{5L}=0\mathrm{}$. The widths and magnitudes of the spectator momentum distributions are strongly energy dependent. This dependence can be reproduced by a plane wave impulse approximation modified by a reflection coefficient calculated semiclassically in WKB approximation.