Optimizing performances of CsI(Tl) crystals with a photodiode readout

Tests are described concerning the performances of CsI(Tl) crystals. Particular care was dedicated to the study of the light production and collection of the crystals, that appear to be significantly affected both by the choice of the wrapping materials and by the details of the binding technique. A functional relation between the light pulse height and the coupling of the crystal+photodiode system was deduced. Finally, the influence of this coupling on the energy resolution of the detector is discussed.