Color Transfer Enhancement for Heavy Quarkonium Production

TL;DR

This paper investigates how color transfer occurs between a heavy quark pair and an unpaired heavy quark or antiquark, revealing a catalyzing process that transforms the pair's color state, with implications for heavy quarkonium production.

Contribution

It introduces a detailed analysis of color transfer mechanisms involving heavy quarks, highlighting the infrared sensitivity and the limitations of current effective field theories.

Findings

Open heavy quarks can catalyze color transformation of quark pairs.

Infrared divergences appear at NNLO in transition probabilities.

Poles depend on kinematic variables, challenging existing EFT matching.

Abstract

We study the transfer of color between a heavy quark pair and an unpaired heavy quark or antiquark moving at a nonrelativistic velocity with respect to the pair. We find that the open heavy quark or antiquark can catalyze the transformation of the pair from octet representation at short distances to singlet at long distances. This process is infrared sensitive in general, and we exhibit double poles in dimensional regularization at next-to-next-to-leading order in the transition probability. Because of their dependence on kinematic variables, these poles cannot be matched to the non-perturbative matrix elements of effective field theories based on a single heavy quark pair.