This study deals with the simulation of the experimental study of Roth
et al. (2000) on the interaction of
energetic Zn projectiles in partially ionized laser produced carbon
targets, and with similar type experiments. Particular attention is paid
to the specific contributions of the K and L shell target electrons to
electron recombination in the energetic Zn ionic projectile. The classical
Bohr–Lindhard model was used for describing recombination, while
quantum mechanical models were also introduced for scaling the L to K
cross-section ratios. It was found that even for a hydrogen-like carbon
target, the effect of the missing five bound electrons brings about an
increase of only 0.6 charge units in the equilibrium charge state as
compared to the cold target value of 23. A collisional radiative
calculation was employed for analyzing the type of plasma produced in the
experimental study. It was found that for the plasma conditions
characteristic of this experiment, some fully ionized target plasma atoms
should be present. However in order to explain the experimentally observed
large increase in the projectile charge state a very dominant component of
the fully ionized plasma must comprise the target plasma. A procedure for
calculating the dynamic evolvement of the projectile charge state within
partially ionized plasma is also presented and applied to the type of
plasma encountered in the experiment of Roth et al. (2000). The low temperature and density tail on the
back of the target brings about a decrease in the exiting charge state,
while the value of the average charge state within the target is dependent
on the absolute value of the cross-sections.
Charge state of Zn projectile ions in partially ionized plasma:
Simulations
