Charge Exchange in Slow Ion-Atom Collisions. Adiabatic Approach

Abstract

This chapter is devoted to consideration of electron-capture processes at very low collision velocities $\upsilon \ll$ 1 a.u. At present time, these processes are of a high importance because of two main reasons: first, they constitute the dominant mechanisms in a low-temperature plasma for creating the impurity ions in excited states, radiation short-wavelength spectra of which are used for plasma diagnostics. Second, at low-energy collisions, electron-capture cross sections, occurring in collisions with hydrogen isotopes (H, D, and T), are strongly influenced by the so-called isotope effect which changes the cross sections values by orders of magnitude. This influence is important for estimating, e.g., the capture cross sections of tungsten atoms and ions, colliding with neutral plasma atoms, because tungsten is adopted now as the most perspective element for making walls and diverter in plasma devices aiming at magnetic plasma confinement.