2 de janeiro de 2019 | Altas Energias, Publicações
Fábio L. Braghin
Phys. Rev. D 99, 014001
02/01/2019
Abstract
Form factors for pion interactions with constituent quarks are investigated as the leading effective couplings obtained from a one-loop background field method applied to a global color model. Two pion field definitions are considered and the resulting eleven form factors are expressed in terms of components of the quark and gluon propagators that compose only two momentum-dependent functions. A momentum-dependent Goldberger-Treiman relation is also obtained as one of the ratios between the form factors. The resulting form factors with pion momenta up to 1.5 GeV are exhibited for different quark effective masses and two different nonperturbative gluon propagators and they present similar behavior to fittings of experimental data from nucleons form factors. The corresponding pseudoscalar averaged quadratic radii (a.q.r.) and correction to the axial a.q.r. are presented as functions of the sea quark effective mass, being equal, respectively, to the scalar and vector ones at the present level of calculation.