Profiles of a positronium beam produced using the photodetachment of positronium negative ions

The characteristics of a positronium beam produced using the photodetachment of positronium negative ions have been investigated. The yields of positronium atoms were in reasonable agreement with the result of particle trajectory simulation including the effects of positronium emission due to recoil of emitted electrons in the photodetachment. The angular divergence of the beam was measured to be 2° (FWHM) at an energy of 2.3 keV.