Optics of large scintillating tiles with wavelength shifting fiber readout — application to a hadron calorimeter

Light yield and response uniformity of a scintillating tile/fiber system were measured for tiles with a side length up to ∼50 cm. With increasing the tile size, the light yield at the tile center decreases and the nonuniformity measured near the tile edges increases gradually. These tile size dependences originate in the light attenuation in the scintillator, and hence are specific to the scintillator type. Radiation hardness of large tile/fiber systems was compared with that of small tile/fiber systems. The SDC barrel hadron calorimeter was used as a model to evaluate the performance of a calorimeter composed of tile/fiber systems with such a lateral nonuniformity and with light yield variation in depth. In the evaluation the hadronic shower profile was given by a GEANT simulation and the Hanging File testbeam data.