EFFECTS OF MASSIVE GLUONS ON QUARKONIA IN LIGHT-FRONT QCD

A constituent parton picture of hadrons with logarithmic confinement a rises naturally in light-front QCD when the hamiltonian is computed us ing a perturbative renormalization group; however, rotational symmetry is not manifest as a simple kinematic symmetry. Relevant operators mu st typically be fine-tuned when a perturbative renormalization group i s used, and in light-front field theory such operators contain functio ns of longitudinal moments. We explore the possibility that a gluon ma ss operator with simple longitudinal momentum dependence may improve a pproximate kinematic rotational symmetry, as revealed by the potential between heavy quarks. (C) 1998 Elsevier Science B.V.