Na(3p←3s) excitation by impact of slow multiply charged ions

We present a systematic experimental and theoretical study of Na(3p{←}3s) excitation by slow (v1 a.u.) singly and multiply charged ions. In particular, the scaling behavior of the respective excitation cross section σNaI with projectile ion charge state q is investigated. Due to the dominance of the competing electron capture channels at low collision energies E, the excitation cross sections deviate significantly from a commonly applied {σ}/q=f(E/q) cross-section scaling relation. {} 1996 The American Physical Society.