Deeply virtual and exclusive electroproduction of omega mesons

Abstract

The exclusive omega electroproduction off the proton was studied in a large kinematical domain above the nucleon resonance region and for the highest possible photon virtuality (Q2) with the 5.75 GeV beam at CEBAF and the CLAS spectrometer. Cross sections were measured up to large values of the four-momentum transfer (-t < 2.7 GeV2) to the proton. The contributions of the interference terms sigma_TT and sigma_TL to the cross sections, as well as an analysis of the omega spin density matrix, indicate that helicity is not conserved in this process. The t-channel pi0 exchange, or more generally the exchange of the associated Regge trajectory, seems to dominate the reaction gamma* p -> omega p, even for Q2 as large as 5 GeV2. Contributions of handbag diagrams, related to Generalized Parton Distributions in the nucleon, are therefore difficult to extract for this process. Remarkably, the high-t behaviour of the cross sections is nearly Q2-independent, which may be interpreted as a coupling of the photon to a point-like object in this kinematical limit.

arXiv comment15 pages,19 figures

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Cited by in corpus (23)

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• Spin Density Matrix Elements in Exclusive rho^0 Electroproduction on 1H and 2H Targets at 27.5 GeV Beam Energy
• Towards a fitting procedure to deeply virtual meson production -- the next-to-leading order case --
• Deeply Virtual Compton Scattering at a Proposed High-Luminosity Electron-Ion Collider
• Exclusive Neutral Pion Electroproduction in the Deeply Virtual Regime
• The pion pole in hard exclusive vector-meson leptoproduction
• Electroproduction of $\varphi (1020)$ mesons at $1.4\le Q^2\le$ GeV${}^2$ measured with the CLAS spectrometer
• Transition distribution amplitudes and hard exclusive reactions with baryon number transfer
• Beam spin asymmetry in deep and exclusive pi0 electroproduction
• Unitarity constraints on neutral pion electroproduction
• Exclusive channels in semi-inclusive production of pions and kaons
• Exclusive Meson Photo- and Electro-production, a Window on the Structure of Hadronic Matter
• Photoproduction of leptophobic bosons
• Exclusive electroproduction and the quark structure of the nucleon
• Unitarity constraints on meson electroproduction at backward angles
• Investigation of electroproduction of $\varphi$ mesons off protons
• Deeply Virtual Exclusive Processes and Generalized Parton Distributions
• Glueball masses and Regge trajectories for the QCD-inspired potential
• Complex Masses of Mesons and Resonances In Relativistic Quantum Mechanics