Scaling laws for electron loss from ion beams

Empirical scaling rules for projectile stripping induced by collisions with argon were extracted by analyzing a large database of experimental cross-sections. By scaling both the cross-sections and the impact velocities, data for single and multiple electron loss from negative ions, neutral particles, and singly or multiply charged positive ions could all be fitted with a single universal curve. At high energies, the scaled data are consistent with a v−1 impact velocity dependence up to scaled velocities of 10. For higher scaled velocities, limited data imply that the velocity dependence becomes v−2. Using our fitted curve, cross-sections are predicted for total and single electron loss from low-charge-state heavy ions of interest for heavy ion fusion and high-energy density research projects. Using a v−2 or a v−1 dependence to extrapolate to energies of 10–20 MeV/u does not strongly influence the predicted magnitude of the total loss cross-sections but does influence the multiple/single loss ratios.