Scalar form factor of the pion in the Kroll-Lee-Zumino field theory
  The renormalizable Kroll-Lee-Zumino field theory of pions and a neutral rho-meson is used to determine the scalar form factor of the pion in the space-like region at next-to-leading order. Perturbative calculations in this framework are parameter free, as the masses and the rho-pion-pion coupling are known from experiment. Results compare favourably with lattice QCD calculations. 
C. A. Dominguez, M. Loewe and M. Lushozi
hep-ph hep-lat