GlueX Project Overviews

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GlueX Project Summaries and Documentation

Introduction to the GlueX Experiment

The following are links to a series of videos on the GlueX experiment. They are meant to provide an introduction to the GlueX experiment for new members of the collaboration. In addition to the videos, the presentations form the video are provided. These are not meant to be complete, but rather a quick way to bring new collaboration members to a basic level of understanding of the experiment.

A Short History of GlueX

This presentation and video present a quick overview of the history of GlueX going from the first meeting in summer 1997 until the present. This is the first of a series of information presentations on the GlueX experiment.

The Photon Facility

This presentation and video present a quick overview of the Hall-D photon facility. It follows the photon beam from production on the diamond radiator through to the photon beam dump, providing a description of each of the detector and beam elements that are part of the process. This is the second of a series of information presentations on the GlueX experiment.

The GlueX Detector

This presentation and video present a quick overview of the GlueX detector in Hall D at Jefferson Lab. It starts with a detector overview, then describes the magnet, liquid hydrogen target and the detector systems in GlueX including the DIRC and the CCAL. It ends with a brief description of the GlueX physics trigger. This is the third of a series of information presentation on the GlueX experiment.

Introductory Lectures on GlueX Physics

Quarks and Mesons

Lecture 1: Fermion Anti-fermion Systems

The lecture discusses building up fermion anti-fermion systems looking at how the spin and orbital momentum combine to form total angular momentum J. It also discusses parity P and charge conjugation C.

Lecture 2: Quarks and Isospin

The lecture discusses isospin and how it is related to up and down quarks. It also builds up systems of 2 and 3 quarks through isospin, and then looks at the isospin of anti-up and anti down quarks, and how mesons are built up with isospin. Finally, isospin and C-parity and used to define G-parity.

Lecture 3: Young's Tableaux and SU(N)

The lecture discusses how to use Young's tableaux to compute products in SU(N). It then specializes to SU(3) and looks at how octets, nonets, decuplets and other representations are built up.

Lecture 4: Mesons in SU(3)

The lecture discusses the how flavour SU(3) from up, down and strange quarks can be used to define the quark content of mesons. Hypercharge is introduced as well as weight diagrams. Finally, mixing between the octet and singlet isospin zero states in a nonet is discussed, and ideal mixing is introduced.

Lecture 5: Strong Decays of Mesons

The lecture discusses how to use the conserved quantum numbers J, P, C, I and G to determine which meson decays are possible. It also discusses the case of identical mesons and how symmetry plays a role in determining allowed decays.

Lecture 6: SU(3) Clebsch-Gordan Coefficients and Meson Decays

The lecture introduces the SU(3) Clebsch-Gordan coefficients that can be used to determine relations between how mesons in a particular nonet decays to two mesons in other nonets. I looks at the four possible decays of octet and singlet states to pairs of mesons, and covers a rarely discussed detail on octets decaying to two octets.

Informational GlueX Notes

Meson Names

Prior to 1986, there was no clear convention for the names of mesons with authors suggesting names with initial observations. There were also mesons that had more than one name, and a number of confused states including the $E/\iota$ puzzle and the $\theta$ meson. In 1986, the Particle Data Group proposed a systematic naming scheme. This document describes that 1986 naming scheme, and provides a translation from the old names to the new ones. It also provides some historical information on the states.

Coordinate Systems

This document describes the different coordinate systems in GlueX and how to move between them. In particilar, events are reconstructed in the GlueX lab frame, while results are generally presented in the center of mass frame. Studies of the decay of mesons produced in GlueX normally occur in the Gottfreid-Jackson and the Helicity frames.

Useful Plots

This document describes the different plots that are useful in GlueX analyses. The plots are based on the production of mesons and baryons, both of which may subsequently decay. The plots discussed are the Chew-Low plot, the Dalitz plot, and the Goldhaber plot. These used independently and together are useful to understand photoproduction reactions in GlueX.

Exotic Meson Production and Decay

This document summarizes the possible photoproduction mechanisms for both normal and exotic-hybrid mesons in GlueX. It then looks at the allowed possible decay modes for the exotic mesons, and summarizes what the detected final states would be. For the normal mesons, the possible photoproduction mechanisms are summarized. Of particular interest is the differences in photoproduction mechanisms for the L=2 vector mesons.

Historical Information on the GlueX Experiment

Gluex detector 3d.jpg

During 2008, the Gluex Detector underwent a series of detailed reviews as part of the Lehman review process. From those reviews, a description of the detector was written that describes both the physics case and the anticipated detector performance: GlueX Project Description A pdf version of the figure is available.

In late 2008, the beamline and tagger for HallD were reviewed. As part of that process, a detailed description of these elements was prepared. That description can be found here: Beamline Documentation


In July 2006, there was a detailed presentation on GlueX to PAC30. The material that was prepared for the PAC is available here: GlueX PAC 30 Documentation
In July 2010, an update was presented to PAC30, it is available here: GlueX PAC 36 Documentation
In June of 2012, a proposal for additional running in GlueX with a focus on the strangonium states was submitted to PAC 39. GlueX PAC 39 Documentation. This proposal would implement a kaon-identification system as well as a software trigger to enable running at higher intensities. This has been conditionally approved, with full approval waiting on the final design of the kaon-identification system. In 2013, the collaboration has submitted a proposal to PAC40 focusing on the physics that can be done only with the enhanced rate capability made possible by the software trigger. GlueX PAC 40 Documentation.

Gluex thumb.jpg In fall of 2011, the GlueX collaboration working with Jefferson Lab put together a Hall-D poster. A thumbnail of the poster is shown to the write, while the 7MByte jpg file suitable for hi-resolution printing at 18" by 24" can be obtained from the GlueX document archive: Hires Poster.