Electroproduction of pions at the threshold: determination of the pion radius and analysis of axial-vector form factor of the nucleon
Esaulov A.S., Titov Yu.N.
We analyze the pion form factor and the nucleon axial-vector form factor, determined from the cross section for electroproduction of pions on protons at threshold with separation of the transverse and longitudinal component. A fit yields a pion radius <ri>1/2 =0.48±0.18 F and an axial mass MA =0.97±0.06 GeV (dipole fit).