The static $Q\bar Q$ interaction at small distances and OPE violating terms

TL;DR

This paper discusses a nonperturbative linear correction to the static quark-antiquark potential at small distances, which helps resolve discrepancies in heavy quarkonium fine splitting and aligns with lattice data, also impacting OPE-violating terms.

Contribution

It introduces a universal linear term in the static potential at small distances due to nonperturbative effects, addressing longstanding issues in heavy quarkonium spectroscopy and lattice comparisons.

Findings

Linear term improves agreement with lattice data

Resolves discrepancies in heavy quarkonium fine splitting

Implications for OPE-violating terms in other processes

Abstract

Nonperturbative contribution to the one-gluon exchange produces a universal linear term in the static potential at small distances $\Delta V=\frac{6N_c \alpha_s \sigma r}{2\pi}$. Its role in the resolution of long--standing discrepancies in the fine splitting of heavy quarkonia and improved agreement with lattice data for static potentials is discussed, as well as implications for OPE violating terms in other processes.