Understanding the Flavor Symmetry Breaking and Nucleon Flavor-Spin Structure within Chiral Quark Model

In $XQM$, a quark can emit Goldstone bosons. The flavor symmetry breaking in the Goldstone boson emission process is used to intepret the nucleon flavor-spin structure. In this paper, we study the inner structure of constituent quarks implied in $XQM$ caused by the Goldstone boson emission process in nucleon. From a simplified model Hamiltonian derived from $XQM$, the intrinsic wave functions of constituent quarks are determined. Then the obtained transition probabilities of the emission of Goldstone boson from a quark can give a reasonable interpretation to the flavor symmetry breaking in nucleon flavor-spin structure.