Modifies a noun

• formation: J W Humberston and P Van Reeth Investigation of positronium formation in positron collisions with atoms having zero threshold energy, Nucl.

• collision: Measurements of differential ionization and positronium collisions are in their infancy.

• scattering: This work will complement the experimental studies of positronium scattering being carried out in the Department.

• atom: Furthermore, Mike Charlton and Helmut Telle are to combine their positron and laser physics backgrounds to initiate spectroscopic investigations of positronium atoms.