Radiation damage of prototype SiPMs for the CMS HCAL Barrel phase I upgrade

Abstract Results from a study of the radiation hardness of silicon photomultipliers (SiPMs) are presented. New ultra high density SiPMs have been recently developed by FBK for the CMS HCAL Barrel phase I upgrade. SiPMs were irradiated to a total dose of 2 × 1 0 12 n ∕ cm 2 (1 MeV equivalent) at the TRIGA reactor at the JSI in Slovenia. The SiPM’s main parameters were measured before and after irradiation. The effects of the neutron radiation on breakdown voltage, signal amplitude, dark current and noise for these devices are shown and discussed.