Performance of the prototype module of the GlueX electromagnetic barrel calorimeter

A photon beam test of the 4 m long prototype lead/scintillating-fibre module for the GlueX electromagnetic barrel calorimeter was carried out in Hall B at the Thomas Jefferson National Accelerator Facility with the objective of measuring the energy and timing resolutions of the module as well as the number of photoelectrons generated. Data were collected over an energy range of 150–650 MeV at multiple positions and angles along the module. Details of the analysis at the centre of and perpendicular to the module are shown herein; the results are σE/E=5.4%/E(GeV)⊕2.3%, σΔT/2=70/E ps, and 660 photoelectrons for 1 GeV at each end of the module.