MPPC photon sensor operational experience in CMS

16th International Conference on Calorimetry in High Energy Physics

Künsken, Andreas^1

III. Physikalisches Institut B, RWTH Aachen University, Otto-Blumenthal-Straße, Aachen

D-52074, Germany^1

关键词: Cell pitches;    Hadron calorimeters;    Hybrid photodiodes;    Multi-pixel photon counters;    Operational experience;    Photon sensors;    Silicon photomultiplier;    System temperature;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/587/1/012022/pdf
DOI  :  10.1088/1742-6596/587/1/012022

来源: IOP

【 摘 要 】

During the first long shutdown of the LHC the Outer Hadron Calorimeter of CMS has been equipped with silicon photomultipliers that replace the existing hybrid photodiodes while maintaining most of the readout chain. The new photon sensors are Hamamatsu MultiPixel Photon Counters with an active area of 3 mm × 3 mm and a cell pitch of 50 μm. Different means of determining the device's breakdown voltage and gain are presented. The stability of the overall system temperature as well as the stability of the gain and the breakdown voltage of the silicon photomultipliers are studied. The correlation between the different methods of determining the gain and breakdown voltage is tested to find whether they yield comparable results.