Total nuclear reaction probabilities for 2 to 6 MeV/nucleon d andHe3in Si

The total nuclear reaction probabilities for 4–13 MeV deuterons and 5–18 MeV ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ ions stopping in Si were measured, in coincidence studies of d${+}^3$He elastic scattering. These probabilities are about 3×${10}^{\mathrm{-}3}$ and 8×${10}^{\mathrm{-}4}$, respectively, for the most energetic d and ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ investigated, and are slightly lower than those predicted using total reaction cross sections ${\sigma }_R$ calculated with the optical model. Evidence of the DeVries-Peng scaling anomaly (deuterons have larger radii but smaller ${\sigma }_R$ than ${}_{}{}^3{}_{}{}^{}\mathrm{He}$) is presented.