Zusammenfassung
Exclusive proton-antiproton annihilation into two photons at large s (similar to10 GeV2) and \t\,\u\similar tos can be described by a generalized parton picture analogous to the "soft mechanism" in wide-angle real Compton scattering. The two photons are emitted in the annihilation of a single fast quark and antiquark. The matrix element describing the transition of the p (p) over bar system to a ...
Zusammenfassung
Exclusive proton-antiproton annihilation into two photons at large s (similar to10 GeV2) and tos can be described by a generalized parton picture analogous to the "soft mechanism" in wide-angle real Compton scattering. The two photons are emitted in the annihilation of a single fast quark and antiquark. The matrix element describing the transition of the p (p) over bar system to a q (q) over bar pair can be related to the timelike proton elastic form factors as well as to the quark/antiquark distributions measured in inclusive deep-inelastic scattering. The reaction could be studied with the proposed 1.5-15 GeV high-luminosity antiproton storage ring (HESR) at GSI.