Performance analysis of silicon photomultiplayer in hadronic endcap calorimeter of CMS detector

After the upgrade in 2016, the CMS experiment started to collect proton-proton collision data with the center of mass √s=13 TeV. From the date specified, the sub-detectors were exposed to high radiation. The accuracy of the signals detected in the sub-detectors is very important in terms of physics analysis. Therefore, the Hadronic Calorimeter (HCAL), one of the sub-detectors of the CMS experiment, should be checked with the latest data taken from the detector. In this thesis study, the efficiency of the Hadronic EndCap (HE) calorimeter, one of the sub-detectors of HCAL, was analyzed with proton-proton collision data in √s=13 TeV center of mass energy taken in 2018.