Heavy Ions Stopping in Plasmas

For the stopping of highly charged heavy ions strong coupling effects in the energy transfer from the projectile-ion to a target plasma become important. A theoretical description of this nonlinear ion stopping has to go beyond the standard approaches like the dielectric linear response or the binary collision model which are strictly valid only at weak ion-target coupling. Here we outline an improved treatment which is based on a suitable combination of binary collision and linear response contributions. This approach well reproduces, up to moderate coupling strengths, the essential features of nonlinear stopping as observed and investigated in numerical simulations, in particular a dependence on the ion charge state like Z^x, with x ≲ 1.5, in contrast to the usual Z² behavior.