Comparative analysis of light-ion ranges in gaseous, liquid, and solid media

详细

Ranges of ions from He to Ne in gaseous (hydrogen and argon), liquid (water), and solid (carbon) media are analyzed. This analysis demonstrates the different dependences of ranges on the velocities, the charges, and the masses of ions in different velocity region. In the case of small ion velocities, the ranges are directly proportional to their velocities and masses and are inversely proportional to the nuclear charge. In the intermediate velocity region corresponding to an ion energy of Е = 0.1–1 MeV/nucleon, in which processes of ion charge exchange play an important role and the average ion charge differs from the nuclear charge, the ranges become proportional to the squared ion velocities and masses and are inversely proportional to the nuclear charge. To establish the relation between the ion ranges in the regions of small and average velocities, it is convenient to use the universal function f(Z, M) = RZ/M, successfully describing the reduced ranges of ions with given velocities in gaseous, liquid, and solid media. In the case of large velocities where ions upon passing through the media lose all electrons, the ranges are directly proportional to the squared ion energies and masses and are inversely proportional to the squared nuclear charge.