Positronium hydride formation in collisions of positrons with molecular hydrogen

Summary The feasibility of observing the threshold for the formation of positronium hydride, PsH, in collisions of low-energy positrons with hydrogen molecules in a mass spectrometric application is considered. The expected count rate of the signature ion H⁺ using existing positron beams depends upon the cross section for a dissociative attachment reaction. The estimation of this cross section relies on knowledge of certain potential energy curves and leptonic wave functions. This knowledge does not yet exist. The curves are roughly estimated by considering the binding of a positron to the ionicB state of H₂. Methods of calculating the wave functions are briefly considered.A preliminary version was presented at the Third International Workshop on Positron and Positronium Chemistry, Milwaukee, July 1990 (Ref. [1])