Engaging Undergraduate Students in Constructing the PbWO₄ Calorimeter for the JEF Experiment at JLab

The JLab Eta Factory (JEF), in experimental Hall D at Jefferson Lab (JLab), will extend the physics reach of the GlueX detector for studies beyond the primary goals of the spectroscopy program. The JEF experiment will enable precision measurements of many of the η and η′ decays, with an emphasis on rare neutral modes. The physics program of the experiment spans from precision tests of low-energy QCD to a search for gauge bosons in the mass range below the mass of the proton, where m_proton∼1 GeV/c². These light gauge bosons putatively couple the SM sector to the dark sector. The JEF experiment requires us to upgrade the inner part of the Forward Calorimeter (FCAL-II) of the GlueX detector with high-granularity, high-resolution lead tungstate (PbWO₄) scintillating crystals. The calorimeter insert is currently under construction at Jefferson Lab. This PbWO₄ Calorimeter will consist of 1600 crystal modules. Ten undergraduate students from four separate universities/colleges are playing a significant role in all aspects in the construction, preparation, testing, and calibration of the crystal modules onsite at JLab. The design of the PbWO₄ crystal modules and the assembling procedure will be discussed in this presentation. The JEF calorimeter upgrade affords the opportunity for engaging undergrads in engaging hands-on research at JLab. Several of the students are presenting posters on their work at this meeting. Please speak to these experts (first ten co-authors) at the poster session to learn more (see: the students' abstract #542375).