On Exclusive Reactions in the Time-Like Region
Authors:
- P. KrollPKP. Kroll
- Th. PilsnerTPTh. Pilsner
- M. SchuermannMSM. Schuermann
- W. SchweigerWSW. Schweiger
Preprint
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 $\eta_c \to p\bar{p}$.