Evidence for Direct Interactions at Low Energy

The angular distributions of protons corresponding to the first excited-state transition in the reaction ${\mathrm{Mg}}^{24}{(p, p^{\prime })}_{1.38\mathrm{M}\mathrm{e}\mathrm{v}}$ have been measured for bombarding energies between 5.0 and 6.2 Mev. The angular correlations between the gamma rays emitted from the first excited state of ${\mathrm{Mg}}^{24}$ and the inelastically scattered protons have been measured at two different bombarding energies and for three proton detection directions. The angular correlation data are fitted to curves of the form $A+B{sin}^2\left[2\right(\theta -{\theta }_q\left)\right]$, where ${\theta }_q$ is the momentum transfer direction for the reaction. The angular correlation data are consistent with predictions of the direct-interaction theory.