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Probing Proton Strangeness with Time-Like Virtual Compton Scattering

Stephen R. Cotanch·Robert A. Williams
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Abstract

We document that p(gamma,e+e-)p measurements will yield new, important information about the off-shell time-like nucleon form factors, especially in the phi meson region (q^2 = M^2_{phi}) governing the phi N couplings g^{V,T}_{ϕN N}. Calculations for p(gamma,e+e-)p, utilizing vector meson dominance, predict measurable phi enhancements at high |t| compared to the expected phi background production from pi, eta and Pomeron exchange. The phi form factor contribution generates a novel experimental signature for OZI violation and the proton strangeness content. The phi N couplings are determined independently from a combined analysis of the neutron electric form factor and recent high |t| phi photoproduction. The pi, eta and Pomeron transition form factors are also predicted and the observed pi and eta transition moments are reproduced.

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Stephen R. Cotanch, Robert A. Williams. 2002-05-22. Probing Proton Strangeness with Time-Like Virtual Compton Scattering. https://doi.org/10.1016/s0370-2693(02)02869-1

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