Studies of Scintillator Tiles with SiPM Readout for Imaging Calorimeters

Imaging hadronic calorimeters with scintillator readout use small scintillator tiles individually read out by silicon photomultipliers to achieve the necessary granularity needed for sophisticated reconstruction algorithms at future collider detectors. For a second generation prototype of the CALICE analog HCAL new, 3 mm thick scintillator tiles with an embedded wavelength shifting fiber and new photon sensor from CPTA are being fabricated. The availability of blue-sensitive SiPMs also allows fiberless coupling of the photon sensor to the tile, a technique requiring modified geometries to achieve a high degree of response uniformity. We discuss results from test bench and from test beam measurements of different scintillator tile geometries as well as prospects for fiberless coupling of photon sensors.