Exotic Hidden-heavy Hadrons and Where to Find Them

TL;DR

This paper explores the theoretical origins of exotic hidden-heavy hadrons using QCD potentials, explaining their energies near thresholds and the properties of certain mesons through fine-tuning of adjoint-meson energies.

Contribution

It introduces a framework connecting adjoint-hadron potentials to the existence and properties of exotic hidden-heavy hadrons in QCD.

Findings

Exotic hidden-heavy hadrons are bound states or resonances in adjoint-hadron potentials.

Many exotic hadrons have energies near heavy-hadron-pair thresholds.

Fine-tuning of adjoint-meson energies explains properties of some exotic mesons.

Abstract

The Born-Oppenheimer potentials for QCD with light quarks include adjoint-hadron potentials that are repulsive at short distances and heavy-hadron-pair potentials that approach thresholds at large distances. The adjoint-hadron potentials must connect smoothly to the heavy-hadron-pair potentials at intermediate distances. We identify exotic hidden-heavy hadrons as bound states and resonances in adjoint-hadron potentials that cross below a heavy-hadron-pair threshold before approaching it. This explains why many exotic hidden-charm and hidden-bottom hadrons have energies near heavy-hadron-pair thresholds. The remarkable properties of some exotic hidden-heavy mesons can be explained by fine tunings of adjoint-meson energies in QCD.