Development of three silicon photomultiplier detector modules for the MAGIC telescopes for a performance comparison to PMTs

The two MAGIC imaging atmospheric Cherenkov telescopes (IACTs) are located on the Canary island of La Palma. Their cameras are currently equipped with more than 1000 photomultiplier tubes (PMTs). We developed a silicon photomultiplier (SiPM) based detector module to evaluate the feasibility of a camera upgrade using only solid state detectors. We combined SiPMs to a composite matrix in order to achieve the same active area as the 1 inch PMTs currently in use. This first prototype was installed in 2015 and is operated alongside the PMTs. Utilizing the collected data, we developed two more SiPM based detector modules. They are equipped with SiPMs from two different suppliers. These three different SiPM based detector modules will enable us to compare three different manufacturers of SiPMs under real observational conditions. Most important is the comparison to the neighbouring PMT modules. (c) 2017 Elsevier B.V. All rights reserved.