Radiative Transitions between Quasimolecular Levels During Energetic Atom-Atom Collisions

Abstract

We report the observation of an x-ray band which cannot be identified as a characteristic atomic x ray either of the target atoms or of the projectiles. The new x ray has been observed when 70-600-keV argon ions impinge on C, Al, Si, and Fe targets. We attribute this x ray to a radiative filling of a vacancy in the $2p\ensuremath{\pi}$ orbital of the Ar-Ar system during the collision.