Gluonic Excitations and Experimental Hall-D at Jefferson Lab

TL;DR

The paper discusses the development of the GlueX experiment at Jefferson Lab, which aims to explore gluonic excitations in mesons using a new polarized photon beam, providing insights into QCD and hybrid mesons.

Contribution

It presents the construction status of the GlueX detector and simulation results for hybrid meson searches, advancing experimental efforts in QCD confinement studies.

Findings

Successful construction of the GlueX detector

Simulation results indicating promising hybrid meson signals

Potential to test QCD predictions on gluonic excitations

Abstract

A new tagged photon beam facility is being constructed in experimental Hall-D at Jefferson Lab as a part of the 12 GeV upgrade program. The 9 GeV linearly-polarized photon beam will be produced via coherent Bremsstrahlung using the CEBAF electron beam, incident on a diamond radiator. The GlueX experiment in Hall-D will use this photon beam to search for and study the pattern of gluonic excitations in the meson spectrum produced through photoproduction reactions with a liquid hydrogen target. Recent lattice QCD calculations predict a rich spectrum of hybrid mesons, that are formed by exciting the gluonic field that couples the quarks. A subset of these hybrid mesons are predicted to have exotic quantum numbers which cannot be formed from a simple $q\bar{q}$ pair, and thus provide an ideal laboratory for testing QCD in the confinement regime. In these proceedings the status of the construction and installation of the GlueX detector will be presented, in addition to simulation results for some reactions of interest in hybrid meson searches.