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On the pion electroproduction amplitude

E. Truhlik
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Abstract

We analyze amplitudes for the pion electroproduction on proton derived from Lagrangians based on the local chiral SU(2) x SU(2) symmetries. We show that such amplitudes do contain information on the nucleon axial form factor F_A in both soft and hard pion regimes. This result invalidates recent Haberzettl's claim that the pion electroproduction at threshold cannot be used to extract any information regarding F_A.

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E. Truhlik. 2001-08-29. On the pion electroproduction amplitude. https://doi.org/10.1103/physrevc.64.055501

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