Readout techniques and radiation damage of undoped cesium iodide

Several readout techniques for undoped CsI have been studied which utilize the fast scintillation component for speed and the high photon yield for good energy resolution. Quantum yields have been measured for samples up to 30 cm in length using photomultiplier tubes, wavelength shifters, and silicon photodiodes. A study has also been made of the scintillation properties of undoped CsI. It is found that the light output and decay time of the 310-nm fast component increases and the emission spectrum shifts to longer wavelengths at lower temperatures. The effects on the optical transmission and scintillation light output due to radiation damage from ⁶⁰Co gamma rays have been measured for doses up to ~10⁶ rad. It is found that the radiation resistance of undoped CsI is substantially higher than has been reported for thallium-doped CsI