Wave functions ofS-wave hadrons in the quenched approximation to lattice QCD

Abstract

We calculate minimal Fock space state wave functions of the $\pi$ and $\rho$ mesons and of the nucleon and delta. The primary discussion is of Coulomb gauge wave functions; we also calculate Landau gauge and gauge-invariant wave functions. The difference in the size of Coulomb and Landau gauge meson wave functions is found to decrease with smaller quark mass. We present parametrizations of wave functions suitable for use as interpolating fields for spectroscopy calculations. When we use wave functions to calculate charge radii of particles (an uncontrolled approximation), we find that their sizes are about one-half the physical values. However, the ratio of the charge radius of the neutron to that of the proton is consistent with the experimental value.