$\omega$ meson from lattice QCD

TL;DR

This paper presents the first lattice QCD calculation of the $oldsymbol{ ext{omega}}$ meson resonance parameters, including a formalism update and an estimate of the $ ext{omega}- ho$ mass difference, aligning well with experimental data.

Contribution

It introduces a pioneering lattice QCD approach to determine the $ ext{omega}$ meson resonance parameters, incorporating an updated three-body formalism and effective field theory matching.

Findings

Resonance pole position at 778.0(11.2)-i3.0(5) MeV matches experimental data.

Estimated $ ext{omega}- ho$ mass difference is 29(15) MeV.

First-ever lattice QCD calculation of $ ext{omega}$ resonance parameters.

Abstract

Many excited states in the hadron spectrum have large branching ratios to three-hadron final states. Understanding such particles from first principles QCD requires input from lattice QCD with one-, two-, and three-meson interpolators as well as a reliable three-body formalism relating finite-volume spectra at unphysical pion mass values to the scattering amplitudes at the physical point. In this work, we provide the first-ever calculation of the resonance parameters of the $\omega$ meson from lattice QCD, including an update of the formalism through matching to effective field theories. The main result of this pioneering study, the pole position of the $\omega$ meson at $\sqrt{s_\omega}= (778.0(11.2)-i\,3.0(5) )\,\mathrm{MeV}$, agrees reasonably well with experiment. In addition we provide an estimate of the $\omega-\rho$ mass difference as $29(15)\,\mathrm{MeV}$.