Penetration of Electrons and Ions in Aluminum

Abstract

The depth of penetration of 0.5‐ to 11‐kev electrons and 1‐ to 25‐kev H⁺, H₂⁺, and He⁺ ions in aluminum has been measured. It has been found that the Thompson‐Whiddington law for electrons does not hold for electrons having energies less than 10 kev. The practical range‐energy relation obtained for electrons in aluminum was found to be R = KE^1.3, where K is 0.042 if E is expressed in kev and R in microns. The practical range‐energy relation for light ions in aluminum was found to be R = KE^0.83 where K = 0.020 for H⁺, K = 0.021 for He⁺, and K = 0.015 for H₂⁺ if E is expressed in kev and R in microns. Results are compared with those obtained by previous observers.