PION DECAY CONSTANT, ELECTROMAGNETIC FORM-FACTOR, AND QUARK ELECTROMAGNETIC SELF-ENERGY IN QUANTUM CHROMODYNAMICS

We examine dynamical chiral symmetry breaking in quantum chromodynamics (QCD). To lowest order in a double perturbation expansion in g, the gauge coupling, and λ=exp(-1bg2) we obtain exact representations for the pion decay constant fπ and electromagnetic form factor Fπ(q2). Using the experimental values for fπ and Fπ(q2), we estimate the dynamically generated quark mass to be 270-300 MeV, in good agreement with a value obtained from e+e- annihilation data. We also calculate the finite electromagnetic self-energy of a quark in QCD and discuss the implications. © 1979 The American Physical Society.