The MICE spectrometers for the measurement of muon beam emittance

Tracking detectors based on 350 ‐ μ m scintillating fibers have been developed to measure muon-beam emittance at the Muon Ionization Cooling Experiment (MICE), the goal of which is to demonstrate ionization cooling by constructing and testing part of a cooling channel designed for a Neutrino Factory. The upstream and downstream trackers were assembled at the Rutherford Appleton Laboratory (RAL) in 2008 and 2009. The mechanical design and construction (including quality assurance) procedures used for the trackers are described in this paper. Results from the cosmic-ray test performed for the upstream tracker at RAL in 2008 are also presented.