Small x divergences in a heavy quark-antiquark state

Abstract

With the current state of similarity renormalisation group approach to light-front QCD, it is possible to address with a degree of generality the issue of light-cone zero modes. We find, contrary to earlier results in a less general framework, that infrared divergences associated with the zero modes do not cancel out in a color singlet heavy quark-antiquark states, except for the lowest order in the nonrelativistic expansion.

Comments: 3 pgs. Talk, originally entitled "Die Hard with Vengence", presented at the Int. Light-Cone Workshop "Light-Cone Physics: Particles and Strings", Trento 2001