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arXiv · 2104.13078

Unitarity constraints on meson electroproduction at backward angles

J. M. Laget
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Abstract

At large virtuality $Q^2$, the coupling to the $ρ$ meson production channels provides us with a natural explanation of the surprisingly large cross section of the $ω$, as well as the $π^+$, meson electroproduction recently measured at backward angles, without destroying the good agreement between the Regge pole model and the data at the real photon point. Together with elastic re-scattering of the outgoing meson it also provides us with a way to explain why the node, that appears at $u\sim -0.15$ GeV$^2$ at the real photon point, disappears at moderate virtuality $Q^2$. Predictions are given for the electroproduction of the $π^0$ meson.

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J. M. Laget. 2021-08-05. Unitarity constraints on meson electroproduction at backward angles. https://doi.org/10.1103/physrevc.104.025202

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