CHARGE-STATE AND NONLINEAR STOPPING POWER OF HEAVY-IONS IN A FULLY IONIZED PLASMA

Due to the high nonequilibrium charge states specific to heavy ions, t he plasma regime with coupling parameters 1/N-D < 1 and Z(p)/N-D > 1 ( N-D similar to number of electrons in a Debye sphere, Z(p) mean charge state of the projectile) is of interest for the applications. In this regime the stopping power cannot be obtained by a linearization of th e Vlasov-Poisson system, but forcing a fully nonlinear treatment. In t he present paper the Vlasov-Poisson system is solved numerically by us ing the capability of the new generation of massively parallel superco mputers. The results are compared with the standard dielectric theory and a binary collision approach. Charge-state calculations are perform ed, accounting for all relevant features of the atomic processes and t he spectra characteristic to heavy ions in dense plasma targets. The r esults show good agreement with experimental measurement for medium an d heavy ions penetrating a Z-pinch device.