Design of a silicon photomultiplier based compact radiation detector for Homeland Security screening

摘要

Next-generation compact radiation detector was studied for more accurate measurement of radiation and improvement of reliability of the detector with purpose of developing of radiation protection technology and military application. The radiation detector which was used previously had some limitations due to the bulky size, limited range and the environment of radiation measurement. On the other hand, the compact radiation detector under this study which has adopted the silicon photomultiplier seems to be suitable for the application because of its physical excellence which are characterized by its small size, high sensitivity and durability. Accordingly, a SiPM based Scintillation detector has been made as a part of basic study of military radiation detector development. The detector has been tested for obtaining the operating characteristics of a sensor and analyzed with variation of parameter values and the efficiency of detection in accordance with the factor of measurement environment of radiation. The two SiPM based Scintillation detectors with the LYSO, BGO and CsI:Tl scintillator were made and the detectors were analyzed with the variation of operating characteristics as reverse bias, operating temperature and high magnetic field that are depend on environmental changes of radiation measurement. The results of three scintillators for a photon count rate and spectra were compared with each other. It was found that there are variations of radiation detection which are characterized by reverse bias, temperature and high magnetic field. Also, It was found that there were the 11.9 % for the LYSO, 15.5 % for BGO and 13.5 % for CsI:Tl energy resolution using array SiPM, and 18 % for CsI:Tl energy resolution using single SiPM, respectively when we measured energy resolution of 511keV for ²²Na. The results demonstrate the potential of SiPM based compact radiation detector to be used widely for Homeland Security applications.