Properties of the (α,α*) Reaction at Very Forward Angles: Coupled-Channels Effects in Single and Mutual Excitation

Use was made of a special feature in the detection of unbound ejectiles, to extend previous measurements of the ($\alpha$,${\alpha }^{*}$) reaction on ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$ and ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$ to very forward angles. The characteristic differential cross sections obtained for mutual as well as for single excitation are well reproduced in a full coupled-channels calculation in which the strong couplings to the first excited $2^{+}$ states of the target nuclei are taken into account.