Excited and exotic charmonium spectroscopy from lattice QCD

TL;DR

This study uses advanced lattice QCD techniques to compute the spectrum of highly excited and exotic charmonium mesons, providing detailed insights into their quantum numbers and potential experimental signatures.

Contribution

It introduces novel computational methods and a large operator basis to reliably identify continuum spins and exotic states in charmonium spectroscopy from lattice QCD.

Findings

Identification of a broad spectrum of excited charmonium states

Detection of states with exotic quantum numbers such as 0+-, 1-+, 2+-

High-precision mass determinations for excited states

Abstract

We present a spectrum of highly excited charmonium mesons up to around 4.5 GeV calculated using dynamical lattice QCD. Employing novel computational techniques and the variational method with a large basis of carefully constructed operators, we extract and reliably identify the continuum spin of an extensive set of excited states, states with exotic quantum numbers (0+-, 1-+, 2+-) and states with high spin. Calculations are performed on two lattice volumes with pion mass approximately 400 MeV and the mass determinations have high statistical precision even for excited states. We discuss the results in light of experimental observations, identify the lightest 'supermultiplet' of hybrid mesons and comment on the phenomenological implications of the spectrum of exotic mesons.