It takes glue to study the "Glue"

One of the main scientific questions that remains unanswered is the nature and behaviour of the "Glue" which holds the quarks together. The puzzling feature of this construction is that quarks are never found free, but only in triplets or pairs; that is known as "confinement". Since gluons carry colour charge, they can form chromoelectric flux tubes, which may result in glueballs or hybrid combinations of gluons and quarks. In certain models, the latter can be produced with JPC quantum numbers not allowed in the simple quark picture. An international experiment (GlueX) is being proposed to search for such exotic hybrid mesons at Jefferson Lab, Virginia, and thus elucidate the phenomenon of confinement. The GlueX program will be presented, with emphasis on the electromagnetic calorimeter R&D at the University of Regina, for which scintillating fibers are glued onto a lead matrix.