The Tail-Catcher/Muon Tracker for the CALICE Test Beam

The CALICE (CAlorimeter for the Linear Collider with Electrons) collaboration [1] plans to examine several technology and geometry options for electromagnetic and hadronic calorimetry at the proposed International Linear Collider. Since in many geometries the total material thickness of the calorimeter is too little to fully contain highly energetic hadronic showers, it is important to gain a good understanding of how to estimate the leakage. In real life, the substantial amount of uninstrumented material in the magnet enveloping the barrel calorimeter will prevent a direct measurement of the energy punching through the calorimeter. The NIU group is responsible for building a detector subsystem consisting of alternating layers of scintillator strips and steel plates to serve the dual purpose of measuring the tail of showers escaping the hadronic calorimeter module, as well as supplement the muontracking capability. This section of the detector, dubbed the “tail-catcher/muon tracker”, or “TCMT”, is rapidly approaching completion. The project involved specification of performance criteria, careful evaluation of available options including emerging technologies, testing of individual components, as well as considerations of costs and other constraints. These are described briefly in the following sections.