Tests of the Peripheral Model for a Cluster Knockout Reaction

Abstract

The reaction $^{6}\mathrm{Li}(\ensuremath{\alpha},2\ensuremath{\alpha})d$ was studied at 50.4, 59.0, 60.5, 70.3 and 79.6 MeV. The angular distributions and energy dependence of the off-energy-shell $\ensuremath{\alpha}\ensuremath{-}\ensuremath{\alpha}$ cross section were extracted and compared with those for free $\ensuremath{\alpha}\ensuremath{-}\ensuremath{\alpha}$ scattering. The agreement between the two is excellent, as predicted by the peripheral model in the quasifree approximation, but the quasifree approximation is not precise enough.