Comparison of Lattice Coulomb-Gauge Wave-Functions in the Quenched Approximation and with Dynamic Fermions
Electromagnetic form-factors; Monte-Carlo calculations; Low 4-momentum; transfer; Wilson fermions; Quantum chromodynamics; QCD; algorithms; scattering; proton; Astronomy & Astrophysics; Physics, Particles & Fields
We present a comparison of Coulomb-gauge wave functions from 6/g2 = 6.0 quenched simulations with two simulations which include the effects of dynamical fermions: simulations with two flavors of dynamical staggered quarks and valence Wilson quarks at 6/g2 = 5.6 and simulations with two flavors of dynamical Wilson quarks and Wilson valence quarks at 6/g2 = 5.3. The spectroscopy of these systems is essentially identical. Parametrizations of the wave functions are presented which can be used as interpolating fields for spectroscopy calculations. The sizes of particles are calculated using these parametrized wave functions. The resulting sizes are small, approximately half the sizes of the physical states. The charge radius of the neutron, which provides an indication of the asymmetries between the wave functions of up and down quarks, is calculated. Although the size of the nucleon in these simulations is small, the ratio of the charge radius of the neutron to that of the proton is consistent with the physical value. We find no significant differences between the quenched and dynamical simulations.
Physical Review D
Hecht, M. W.; Bitar, K. M.; Degrand, T.; Edwards, R.; Gottlieb, S.; Heller, U. M.; Kennedy, A. D.; Kogut, J. B.; Liu, W.; Ogilvie, M. C.; Renken, R. L.; Rossi, P.; Sinclair, D. K.; Sugar, R. L.; and Wang, K. C., "Comparison of Lattice Coulomb-Gauge Wave-Functions in the Quenched Approximation and with Dynamic Fermions" (1993). Faculty Bibliography. 1920.