The effect of radiation damage on the light yield and uniformity of candidate plastic scintillator tiles for the CMS hadron calorimeter upgrade

A study is presented of the effects of radiation damage on various plastic scintillating tiles considered for the LHC Run 3 upgrade of the hadron calorimeter of the CMS detector. Measurements are made both before and after irradiation in the CMS collision hall to a dose of 44 kGy. Results are given for their energy spectrum, efficiency as a function of position, and light yield; tiles of different shapes were studied. All tiles saw a light reduction of $\approx 50\%$. The tiles in the shape currently used in the CMS detector did not see increased non-uniformity of light collection, while a significant disuniformity was observed in tiles in an alternative shape.