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arXiv · 1112.1533

Theory of time-like baryon form factors near thresholds

Yu. A. Simonov
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Abstract

A new mechanism of baryon-antibaryon production via nonperturbative double pair creation in intermediate mesons is proposed and the theory contains no fitting parameters. It is shown, that near-threshold resonances are responsible for enhancements in electroproduction cross sections: $ψ(4S)$ for $Λ^+_c Λ^-_c, Υ(6S)$ for $Λ_b \bar Λ_b$. An admixture of intermediate $D$- wave resonances produces angular dependence in differential cross section and can explain unusual behavior of the ratio $G_E/G_M$ for the proton.

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Yu. A. Simonov. 2011-12-07. Theory of time-like baryon form factors near thresholds. https://doi.org/10.1103/physrevd.85.125025

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