  Magneto optical trap recoil ion momentum spectroscopy is used to measure
energy-dependent charge exchange cross sections in the Cs+ + Rb(5s, 5p) system
over a range of projectile energies from 3.2 to 6.4 keV. The measurements are
kinematically complete and yield cross sections that are differential in
collision energy, scattering angle, and initial and final states.
