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arXiv · hep-ph/9509267

Soft Contribution to Form Factors of $γ^* p \to Δ^+$ Transition

V. M. Belyaev·A. V. Radyushkin
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Abstract

The purely nonperturbative soft contribution to the $γ^* p \to Δ^+$ transition form factors is estimated using the local quark-hadron duality approach. Our results show that the soft contribution is dominated by the magnetic transition: the ratio $G_E^*(Q^2)/G_M^*(Q^2)$ is small for all accessible $Q^2$, in contrast to pQCD expectations that $G_E^*(Q^2) \to -G_M^*(Q^2)$. We also found that the soft contribution to the magnetic form factor is large enough to explain the magnitude of existing experimental data.

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V. M. Belyaev, A. V. Radyushkin. 1995-09-15. Soft Contribution to Form Factors of $γ^* p \to Δ^+$ Transition. https://doi.org/10.1103/physrevd.53.6509

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