Vacuum structure,chiral symmetry breaking and electric dipole moment of neutron

Considering a CP-violating QCD interaction, the electric dipole moment of neutron (EDMN) is estimated in a quark model of light mesons with a dynamical breaking of chiral symmetry through a non-trivial vacuum structure. Pion and kaon, being treated consistently within the model, yield to the constituent quark wave functions as well as the dynamical quark masses and thus determine the constituent quark field operators with respect to light quark flavors. Using the translationally invariant hadronic states and these constituent quark field operators, the EDMN estimated here remains well within the recent experimental bound ofD _n<11 × 10⁻²⁶ e-cm with the CP-violation parameter |ϑ|=10⁻⁸, which in fact accounts for a strong CP-violation.