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arXiv · hep-ph/9305251

On Exclusive Reactions in the Time-Like Region

P. Kroll·Th. Pilsner·M. Schuermann·W. Schweiger
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Abstract

The electromagnetic form factors of the proton in the time-like region and two-photon annihilations into proton-antiproton are investigated. To calculate these processes at moderately large $s$ we use a variant of the Brodsky-Lepage hard-scattering formalism where diquarks are considered as quasi-elementary constituents of baryons. The proton wave function and the parameters controlling the diquark contributions are determined from fits to space-like data. We also comment on the decay $η_c \to p\bar{p}$.

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P. Kroll, Th. Pilsner, M. Schuermann, W. Schweiger. 1993-05-17. On Exclusive Reactions in the Time-Like Region. https://doi.org/10.1016/0370-2693(93)91042-l

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