1996/05/22 by T. Arens, M. Diehl, O. Nachtmann +1 · 3 citations
Physics and Astronomy · #hep-ph
published as Z.Phys. C74 (1997) 651-669 · 45 pages (LaTeX), 7 figures as separate postscript files
arxiv created 1996/05/22 · arxiv updated 2009/11/30
We discuss the reaction e p → e p X in the one-photon exchange approximation, where it is in essence the reaction γ* p → p X. A large rapidity gap is required between the particle or particles of the proton remnant p and those of X. We define a suitable azimuthal angle φ between a leptonic and a hadronic plane. The dependence of the cross section on φ is given explicitly and can be used to extract cross sections and interference terms for the reaction γ* p → p X corresponding to the various helicities of the virtual photon γ*. The interference terms can be used to test models for the large rapidity gap events in a sensitive way. We discuss in detail models with factorizing Pomeron exchange and in particular the Donnachie-Landshoff Pomeron model. We make some remarks on soft colour exchange models and on possible effects of QCD background vacuum fields. We conclude with a suggestion to look for Odderon exchange in exclusive deep inelastic high energy reactions like γ* p → p π0 and γ* p → p η.