LYSO scintillator studies for a fast low-energy calorimeter

Detector cells consisting of fast LYSO crystals viewed by avalanche photo-diodes were designed, built and bench-tested. Using two avalanche photo-diodes per crystal and using fast pulse shaping provided the light yield, low noise, and fast response needed for use in 50 MeV calorimetry for high beam rates. The achieved stochastic term coefficient is 0.17% and the time response was characterized by a single decay term of 50 ns.