In a plasma source development of a hydrogen pair-ion plasma consisting of only hydrogen atomic ions, H and H−, efficient production of the atomic ions is required. Hydrogen positive ions produced in a PIG discharge are supplied to a catalyst. The ions are converted to the atomic ions on the catalyst surface, and an ionic plasma with very low electron density is generated.

Radiative corrections due to pair production in process of electron–positron annihilation are considered. The main attention is paid to the corrections of the third order. Simultaneous emission of photons and pairs is taken into account. The leading log approximation and convolution procedure are used. Exponentiation is discussed. Theoretical uncertainty in description of higher order secondary...

The process of electron-positron pair production by axion propagating in an external magnetic field is investigated in a model with only induced axion coupling to leptons. Contributions of the lowest and higher Landau levels are analyzed. The results we have obtained demonstrate a strong catalyzing influence of the field.

We present first observations of the transversity parton distribution based on an analysis of pion-pair production in deep-inelastic scattering off transversely polarized targets. The extraction of transversity relies on the knowledge of dihadron fragmentation functions, which we take from electron-positron annihilation measurements. This is the first attempt to determine the transversity distr...