Determination of working channels in the Aerogel RICH of Belle II spectrometerBrenčič, Žiga (Avtor) Križan, Peter (Mentor) Pestotnik, Rok (Komentor) Cherenkov radiationCherenkov detectorsStandards and calibrationSpectrometers and spectroscopic techniquesExperimental methods and instrumentation for elementary-particle and nuclear physicsData analysis.In 2018, the accelerator SuperKEKB in Japan and the Belle II spectrometer started their operations. At the beginning of a spectrometer operation researchers began the calibration process of all sub-detectors. In this master thesis we present the calibration of the Aerogel Ring Imaging Cherenkov detector (ARICH). ARICH sub- detector consists of an aerogel plane and a position-sensitive photon detector plane. We explore which channels of the photon detector detected photons when there were not any photons present and which channels have never detected any photons at all. Then we investigate how the number of none working channels changes throughout the Belle II spectrometer operation. In the end we explore how the none working channels influence the measurements of the Cherenkov angle.20202020-01-09 07:45:03Magistrsko delo/naloga113461VisID: 106270COBISS_ID: 3401060sl