Characterization of FBK NUV-HD SiPMs for the pSCT camera proposed for the Cherenkov Telescope Array

Recent developments on Silicon Photomultipliers (SiPMs) have shown that they are particularly adequate to detect fast signal due to low-intensity light. Fondazione Bruno Kessler (FBK) has optimized these sensors for the Near-Ultraviolet Cherenkov light emitted by high energy gamma-ray showers in the atmosphere. The FBK high density SiPMs (NUV-HD) have been extensively characterized in the laboratories of the Italian Institute of Nuclear Physics (INFN) in view of equipping the focal plane camera of the Schwarzschild-Couder Telescope prototype (pSCT) in the framework of the Cherenkov Telescope Array (CTA). Here we report the performances of the 6 × 6 SiPMs based on 40 × 40 cells, in terms of gain and signal-to-noise ratio. We compare the results obtained on devices from the latest generation and grown on different substrates in order to choose the most suitable sensor for the pSCT camera