Chiral anomaly and the pion properties in the light-front quark model

Abstract

We explore the link between the chiral symmetry of QCD and the numerical results of the light-front quark model, analyzing both the two-point and three-point functions of the pion. Including the axial-vector coupling as well as the pseudoscalar coupling in the light-front quark model, we discuss the implication of the chiral anomaly in describing the pion decay constant, the pion-photon transition form factor and the electromagnetic form factor of the pion. In constraining the model parameters, we find that the chiral anomaly plays a critical role and the analysis of Fπγ(Q2) in timelike region is important. Our results indicate that the constituent quark picture is effective for the low and high Q2 ranges implementing the quark mass evolution effect as Q2 grows.