Mitroy, Jim and Ivanov, Igor A. (2001). Measuring the positron affinities of atoms: II. Journal of Physics B: Atomic, Molecular and Optical Physics,34(5):121-129.
It has been proposed that the binding energies of positrons to a number of atoms can be determined by the charge transfer reaction A(-) + e(+) --> e(+)A + e(-). This reaction can be realized in the laboratory by intersecting a negative ion beam with a positron beam. The existence of e(+)A and the determination of its binding energy can be shown by detecting the charge transfer electrons and measuring their energies.
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