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Nucleon electromagnetic form factors and polarization observables in space-like and time-like regions

Egle Tomasi-Gustafsson·F. Lacroix·C. Duterte·G. I. Gakh
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Abstract

We perform a global analysis of the experimental data of the electromagnetic nucleon form factors, in space-like and time-like regions. We give the expressions of the observables in annihilation processes, such as $p+\bar{p}\to \ell^+ +\ell^- $, $\ell=e$ or $μ$, in terms of form factors. We discuss some of the phenomenological models proposed in the literature for the space-like region, and consider their analytical continuation to the time-like region. After determining the parameters through a fit on the available data, we give predictions for the observables which will be experimentally accessible with large statistics, polarized annihilation reactions.

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Egle Tomasi-Gustafsson, F. Lacroix, C. Duterte, G. I. Gakh. 2005-03-01. Nucleon electromagnetic form factors and polarization observables in space-like and time-like regions. https://doi.org/10.1140/epja%2Fi2005-10030-6

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