This report presents a design system based on the use of CsI(TI) detectors to search for lost radioactive sources that are dangerous and harmful to individuals, including searching persons. For this purpose, the GEANT...This report presents a design system based on the use of CsI(TI) detectors to search for lost radioactive sources that are dangerous and harmful to individuals, including searching persons. For this purpose, the GEANT4 simulation toolkit was utilized to develop a system based on three detectors. Various simulated analyses were performed on the dose rates of the three detectors using different source–detector distances and detector separation. There were good agreement between the simulated results and the experimentally measured data. A new method was discussed to detect and search for radioactive sources based only on the dose rates in detectors with source activity. Numerical analyses were performed based on the measured dose rates and the difference of distances to determine the actual location of the lost single or multiple γ-ray sources at a specific angle. The detection limit was calculated from the background radiation to establish the sensitivity and capability of the proposed detector system. This system can be applied in fields in which it is necessary to locate unknown radioactive sources.展开更多
The performance test of a CsI(Tl) crystal (70×27×23 mm3) was performed by applying the pulse shape discrimination technique for identification of light charged particles .The crystal is coupled to a photomul...The performance test of a CsI(Tl) crystal (70×27×23 mm3) was performed by applying the pulse shape discrimination technique for identification of light charged particles .The crystal is coupled to a photomultiplier tube during an experiment with 6He beam.The pulse waveform is fully recorded by employing a high precision digital oscilloscope.The fast and slow gates are used for the pulse shape discrimination and the best values for the gate widths were determined to be 0.5 μs and 1.67 μs,respectively.The 6He,4He and 3He are successfully discriminated with this technique.展开更多
基金Xi’an Jiaotong University and was fully supported by key research and development plan of Shandong Province(No.2017CXGC0916)and the Chinese government
文摘This report presents a design system based on the use of CsI(TI) detectors to search for lost radioactive sources that are dangerous and harmful to individuals, including searching persons. For this purpose, the GEANT4 simulation toolkit was utilized to develop a system based on three detectors. Various simulated analyses were performed on the dose rates of the three detectors using different source–detector distances and detector separation. There were good agreement between the simulated results and the experimentally measured data. A new method was discussed to detect and search for radioactive sources based only on the dose rates in detectors with source activity. Numerical analyses were performed based on the measured dose rates and the difference of distances to determine the actual location of the lost single or multiple γ-ray sources at a specific angle. The detection limit was calculated from the background radiation to establish the sensitivity and capability of the proposed detector system. This system can be applied in fields in which it is necessary to locate unknown radioactive sources.
基金Supported by National Basic Research Program (973 Program) of China (2007CB815002)NSFC (10775003,10827505)
文摘The performance test of a CsI(Tl) crystal (70×27×23 mm3) was performed by applying the pulse shape discrimination technique for identification of light charged particles .The crystal is coupled to a photomultiplier tube during an experiment with 6He beam.The pulse waveform is fully recorded by employing a high precision digital oscilloscope.The fast and slow gates are used for the pulse shape discrimination and the best values for the gate widths were determined to be 0.5 μs and 1.67 μs,respectively.The 6He,4He and 3He are successfully discriminated with this technique.
