Measurement of the Average Equilibrium Charge of Fast Heavy Ions in a Solid byH+Emission at the Exit Surface

Abstract
The H+ secondary-ion yield from the surface of solid targets of Au, C, and nitrocellulose has been used to measure mean charges of energetic ions of Kr84 and Ar40 (at 1.16 MeV/u) at the beam-exit surface. Values for Kr ions were found to be 1.6 to 3 electronic charges (e) less than those found 70 ns later, after Auger decay. No such difference was observed for Ar ions of the same velocity.