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Small x divergences in a heavy quark-antiquark state

Martina Brisudova
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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.

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Martina Brisudova. 2001-11-29. Small x divergences in a heavy quark-antiquark state. https://doi.org/10.1016/s0920-5632(02)01324-5

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