Atomic scattering from oriented Rydberg atoms

Highly‐excited and oriented Rydberg atoms of varying angular momenta are being used to study atomic interactions. The ‘‘exotic’’ semiclassical properties of these atoms present an opportunity for fine control of dynamic pathways. We report initial application of oriented Rydberg atoms to collision studies of electron capture by protons and positrons at intermediate collision speeds. Several novel features have been revealed, such as the double‐peak structures predicted in the angular scattering of projectiles under certain orientations. These structures are traced to the Thomas two‐step capture mechanism.