Spectroscopic investigation of the ($alpha$,2$alpha$) reaction

Nine target nuclei $sup 12$C, $sup 16$O, $sup 24$,$sup 26$Mg, $sup 28$,$sup 30$Si, $sup 40$,$sup 44$Ca, and $sup 66$Zn have been studied by the ($alpha$,2$alpha$) reaction with an incident alpha beam energy of 90 MeV. Energy resolution of 250-300 keV (FWHM) permitted identification of many excited states, although the ground state transitions were dominant. The ground state angular correlation cross section magnitudes decreased a factor of ten from $sup 12$C to $sup 66$Zn. In all cases the data appear to be consistent with a quasifree $alpha$-$alpha$ collision description of the reaction process. (auth)