Application of a stopping power formula to channeled ions

Abstract A formula based on a modification and extension of the Firsov theory for the electronic stopping cross section has been fit to experimental data for helium ions incident on silicon. This formula was previously found to give a good fit to all available data for gaseous targets. We demonstrate here that it also applies for ions in solids for both random and channeled incidence. The parameters of the formula are given for helium incident along random directions and along ⟨111⟩, ⟨110⟩, and {111}. The results suggest that proper channeled particles contribute significantly to the ⟨110⟩ energy loss spectra at energies below 400 keV