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Vector meson dominance pion electromagnetic form factor with the sigma-model loop corrections

S. K. Dubinsky·A. Yu. Korchin·N. P. Merenkov
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Abstract

A model is developed for electromagnetic form factor of the pion. One-loop corrections are included in the linear sigma-model. The rho-meson contribution is added in an extended VMD model. The form factor, calculated without fitting parameters, is in a good agreement with experiment for space-like and time-like photon momenta. Loop corrections to the two-pion hadronic contribution a^{(had, π)}_μto the muon anomalous magnetic moment are calculated. The optimal value of the sigma-meson mass appears to be close to the rho-meson mass.

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S. K. Dubinsky, A. Yu. Korchin, N. P. Merenkov. 2004-07-16. Vector meson dominance pion electromagnetic form factor with the sigma-model loop corrections. https://doi.org/10.1134/1.1800179

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