Absolute spectroscopic factors from the (p,p. cap alpha. ) reaction at 100 MeV on 1p-shell nuclei

The ($p, p\ensuremath{\alpha}$) reaction on $^{6}\mathrm{Li}$, $^{7}\mathrm{Li}$, $^{9}\mathrm{Be}$, and $^{12}\mathrm{C}$ has been investigated experimentally at a bombarding energy of 100 MeV. Data were obtained at a large number of angle pairs in order to study the reaction mechanism. The data are in good agreement with distorted-wave impulse-approximation calculations; unlike most analyses of transfer reactions we obtain absolute $\ensuremath{\alpha}$-particle spectroscopic factors. These are in good agreement with $1p$ shell model predictions. Thus we find no evidence for additional $\ensuremath{\alpha}$-particle-like correlations.