Commissioning, characterisation and temperature stabilisation of a 22000 channel SiPM-on-tile hadron calorimeter system

With the successful construction and operation of a highly granular hadron calorimeter system, featuring <math display="inline" id="d1e189" altimg="si18.svg"><mo>∼</mo></math>22000 individually read out SiPM-on-tile channels, the CALICE collaboration has set the next milestone in proving the scalability of the concept for a future high energy linear collider experiment. For this large sample of photosensors a new approach of quality control was required to sufficiently characterise and monitor device parameters for both, test bench and in-situ beam test data. In the presence of temperature fluctuations during operation, it was possible to stabilise the SiPM responses with a fully automated adjustment of the bias voltage based on frequent temperature measurements, thanks to the excellent parameter uniformity of the devices. This contribution presents the results of SiPM parameter studies during the construction and commissioning phase and reports about the system performance and the experience of automated temperature compensation at system level during operation.