Searches for Exotic Hadrons at GlueX

TL;DR

The GlueX experiment aims to discover hybrid mesons to understand gluonic excitations in QCD, utilizing a high-quality photon beam and spectrometer to analyze meson spectra and exotic states.

Contribution

This paper reports on the analysis of unprecedented photoproduction data from GlueX, including polarization measurements and insights into hybrid mesons and pentaquark candidates.

Findings

Measurement of polarization observables in meson production

Spectroscopic progress on light mesons

Photoproduction data near J/ψ threshold

Abstract

The search for hybrid mesons and the detailed study of their spectrum is the primary goal of the GlueX Experiment in Hall D at Jefferson Lab. The identification and study of hybrid mesons promises to provide unique insight into gluonic degrees of freedom in QCD and the nature of confinement. The experiment combines an intense photon beam with linear polarization peaking around 9 GeV incident on a liquid hydrogen target with a nearly hermetic spectrometer, allowing for the comprehensive study of charged and neutral particle final states. The first phase of the experiment has recently concluded, yielding a photoproduction data set of unprecedented size and quality. We report on the status of the analysis of this data, including measurements of polarization observables, progress in spectroscopic measurements of light mesons, and the measurement of the photoproduction of $J/\psi$ near threshold, which is providing critical insight into the nature of the LHCb closed-charm pentaquark candidates.