STATE-SELECTIVE ELECTRON-CAPTURE FOLLOWING AR8-LI COLLISIONS FOR IMPACT ENERGIES FROM 0.1-KEV-AMU(-1) TO 1.0-KEV-AMU(-1)()

The effect of the velocity of the incident ions in the nl-distribution s for n = 8 and 9 of the electron capture in collisions of highly char ged Ar8+ ions with a lithium target is studied in the 0.1-1 keV amu(-1 ) energy range. The experimental nl-distributions are deduced from the measured emission cross sections of all lines corresponding to 7l'-8l and 8l'-9l transitions. The results of theoretical calculations using the three-body classical trajectory Monte Carlo (CTMC) method are pre sented for the Ar8+-Li(2s) system and also for the O8+-Li(2s) system i n order to show the influence of the Ar8+ core electrons on the find n e-distributions. The experimental and theoretical results are found to be in fair agreement except for the 9s and 9p cross sections. The pre sence of the projectile core electrons strongly affects the population and the collision energy dependence of low-l values produced in the e lectron capture reaction. In particular, the sigma(nl) partial cross s ections (n = 8, 9 and l = 0, 1, 2) increase with decreasing energies a nd go through a maximum for sigma(8s) and sigma(8p). Electronic energy curve calculations for the (Ar7+ + Li)(+) and (O7+ + Li)(+) systems a llow us to discuss the results in terms of dynamical couplings.