Energy-gain spectroscopy of electron-capture collisions between low-energy Ar and Ne projectiles and atomic and molecular deuterium targets

Translational energy-gain spectroscopy is used to determine the final-state (nl) populations following single-electron capture by ${\mathrm{Ar}}^{\mathrm{q}+}$ (q=4–8) and ${\mathrm{Ne}}^{\mathrm{q}+}$ (q=4–7) projectiles in atomic and molecular deuterium targets at an energy of 545q eV. The importance of kinematics in analyzing these systems is discussed. The final-state populations are found to be very sensitive to the energy-level structure of the collision system. The results are interpreted in terms of a ‘‘reaction window’’ in the energy gain which is calculated using a multichannel Landau-Zener model.