The PCAC relation in the NJL model in the BS/Faddeev approach Original Research Article

Evaluations of bound state expectation values of quantized one-body operators in the canonical operator formalism are reviewed, based on the Bethe-Salpeter(BS)/Faddeev approach in the NJL model. The PCAC relation in the BS/Faddeev approach is derived without assuming any particular form of the Bethe-Salpeter kernel. These results are applied to ladder truncation schemes and the truncation scheme in which the qq interactions induced by the qq̄ exchange in the pion and sigma mesonic channel are included.