Comparison Between Reactions of Alpha Particles With Scandium-45 and Deuterons with Titanium-47

The excitation functions for the ($\alpha , n$), ($\alpha , 2n$), ($\alpha , 2p$), ${(\alpha , {\alpha }^{\prime }n)}^m$, ${(\alpha , {\alpha }^{\prime }n)}^g$, and ($\alpha , 2pn$) reactions of ${\mathrm{Sc}}^{45}$ and the ($d, n$), ($d, 2n$), ($d, 2p$), ${(d, \alpha n)}^m$, and ${(d, \alpha n)}^g$ reactions of ${\mathrm{Ti}}^{47}$ were measured for alpha-particle energies from 15 to 40 MeV and for deuteron energies from 4 to 20 MeV. The alpha-particle excitation functions can be successfully fitted by a calculation based upon compound-nucleus theory; but the calculation is less successful in reproducing the deuteron excitation functions. The divergences between calculation and observation are in a direction that is to be expected from the contribution of deuteron stripping reactions. Despite the indications that the deuteron-induced reactions have substantial noncompound contributions, the ratio of the cross sections for the ($\alpha , 2p$) and ($\alpha , 2n$) reactions have the same dependence upon the excitation energy of the compound system as has the corresponding ratio for the ($d, 2p$) and ($d, 2n$) reactions.