本文采用涂布法制备了一系列H310BO3/ZnS(Ag)闪烁体转换屏样品,对其成分配比进行了优化。结果表明,最佳的H310BO3/ZnS(Ag)质量比在1∶6～1∶7之间,最佳的黏合剂用量为总质量的25%。利用中子照相设备对转换屏的发光均匀性进行了成像分析...本文采用涂布法制备了一系列H310BO3/ZnS(Ag)闪烁体转换屏样品,对其成分配比进行了优化。结果表明,最佳的H310BO3/ZnS(Ag)质量比在1∶6～1∶7之间,最佳的黏合剂用量为总质量的25%。利用中子照相设备对转换屏的发光均匀性进行了成像分析,结果显示光输出非常均匀;对楔形镉条进行中子成像,并采用调制传递函数(modulation transfer function,MTF)方法计算了系统分辨率,结果显示,在MTF值为0.1时,对于厚度分别为270(11)、350(14)、404(9)及505(15)μm的转换屏,其相应的系统空间分辨率分别为255.6、315.9、371.0和471.3μm。展开更多
Chinese Spallation Neutron Source(CSNS) has successfully produced its first neutron beam in 28th August 2017. It has been running steadily from March, 2018. According to the construction plan, the engineering material...Chinese Spallation Neutron Source(CSNS) has successfully produced its first neutron beam in 28th August 2017. It has been running steadily from March, 2018. According to the construction plan, the engineering materials diffractometer(EMD) will be installed between 2019–2023. This instrument requires the neutron detectors with the cover area near3 m2in two 90° neutron diffraction angle positions, the neutron detecting efficiency is better than 40%@1A, and the spatial resolution is better than 4 mm×200 mm in horizontal and vertical directions respectively. We have developed a onedimensional position-sensitive neutron detector based on the oblique6Li F/Zn S(Ag) scintillators, wavelength shifting fibers,and Si PMs(silicon photomultipliers) readout. The inhomogeneity of the neutron detection efficiency between each pixel and each detector module, which caused by the inconsistency of the wave-length shifting fibers in collecting scintillation photons, needs to be mitigated before the installation. A performance optimization experiment of the detector modules was carried out on the BL20(beam line 20) of CSNS. Using water sample, the neutron beam with Φ5 mm exit hole was dispersed related evenly into the forward space. According to the neutron counts of each pixel of the detector module, the readout electronics threshold of each pixel is adjusted. Compared with the unadjusted detector module, the inhomogeneity of the detection efficiency for the adjusted one has been improved from 69% to 90%. The test result of the diffraction peak of the standard sample Si showed that the adjusted detector module works well.展开更多
A simulation of the properties of the shifting scintillator neutron detector using 6LiF/ZnS(Ag) scintillation screens is performed.The simulation results show that the light attenuation length of standard BC704 scinti...A simulation of the properties of the shifting scintillator neutron detector using 6LiF/ZnS(Ag) scintillation screens is performed.The simulation results show that the light attenuation length of standard BC704 scintillator is about 0.65 mm.Its thermal neutron detection efficiency,gamma sensitivity and intrinsic spatial resolution can achieve around 50.0%,10 5and 0.18 mm(along X-axis) respectively.For the detector,air coupling position resolution is better than the silicone oil coupling.Some of the simulation results are compared with experimental results.They are in agreement.This work will be helpful for constructing neutron detector for high intensity powder diffractometer at Chinese spallation neutron source.展开更多
The investigation of a novel thermal neutron detector is developed to fulfill the requirements of the high intensity power diffractometer （HIPD） at the Chinese Spallation Neutron Source （CSNS）. It consists of two ...The investigation of a novel thermal neutron detector is developed to fulfill the requirements of the high intensity power diffractometer （HIPD） at the Chinese Spallation Neutron Source （CSNS）. It consists of two layers of 6LiF/ZnS（Ag） scintillators, two layers of crossed WLSF arrays, several multi-anode photo multiplier tubes （MA-PMT）, and the matching readout electronics. The neutron detection efficiency of the scintilltors, the light transportation ability of the WLSF, and the spatial linearity of the readout electronics are measured and discussed in this paper. It shows that the sandwich structure and the compact readout electronics could fulfill the needs of the HIPD. A prototype with a 10 cm×10 cm sensitive area has been constructed to further study the characteristics of the neutron scintillator detector.展开更多
文摘本文采用涂布法制备了一系列H310BO3/ZnS(Ag)闪烁体转换屏样品,对其成分配比进行了优化。结果表明,最佳的H310BO3/ZnS(Ag)质量比在1∶6～1∶7之间,最佳的黏合剂用量为总质量的25%。利用中子照相设备对转换屏的发光均匀性进行了成像分析,结果显示光输出非常均匀;对楔形镉条进行中子成像,并采用调制传递函数(modulation transfer function,MTF)方法计算了系统分辨率,结果显示,在MTF值为0.1时,对于厚度分别为270(11)、350(14)、404(9)及505(15)μm的转换屏,其相应的系统空间分辨率分别为255.6、315.9、371.0和471.3μm。
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11975255 and 11875273)Guangdong Basic and Applied Basic Research Foundation (Grant No. 2020B1515120025)。
文摘Chinese Spallation Neutron Source(CSNS) has successfully produced its first neutron beam in 28th August 2017. It has been running steadily from March, 2018. According to the construction plan, the engineering materials diffractometer(EMD) will be installed between 2019–2023. This instrument requires the neutron detectors with the cover area near3 m2in two 90° neutron diffraction angle positions, the neutron detecting efficiency is better than 40%@1A, and the spatial resolution is better than 4 mm×200 mm in horizontal and vertical directions respectively. We have developed a onedimensional position-sensitive neutron detector based on the oblique6Li F/Zn S(Ag) scintillators, wavelength shifting fibers,and Si PMs(silicon photomultipliers) readout. The inhomogeneity of the neutron detection efficiency between each pixel and each detector module, which caused by the inconsistency of the wave-length shifting fibers in collecting scintillation photons, needs to be mitigated before the installation. A performance optimization experiment of the detector modules was carried out on the BL20(beam line 20) of CSNS. Using water sample, the neutron beam with Φ5 mm exit hole was dispersed related evenly into the forward space. According to the neutron counts of each pixel of the detector module, the readout electronics threshold of each pixel is adjusted. Compared with the unadjusted detector module, the inhomogeneity of the detection efficiency for the adjusted one has been improved from 69% to 90%. The test result of the diffraction peak of the standard sample Si showed that the adjusted detector module works well.
基金supported by the National Natural Science Foundation of China(Grant No.11175257)
文摘A simulation of the properties of the shifting scintillator neutron detector using 6LiF/ZnS(Ag) scintillation screens is performed.The simulation results show that the light attenuation length of standard BC704 scintillator is about 0.65 mm.Its thermal neutron detection efficiency,gamma sensitivity and intrinsic spatial resolution can achieve around 50.0%,10 5and 0.18 mm(along X-axis) respectively.For the detector,air coupling position resolution is better than the silicone oil coupling.Some of the simulation results are compared with experimental results.They are in agreement.This work will be helpful for constructing neutron detector for high intensity powder diffractometer at Chinese spallation neutron source.
基金Supported by National Natural Science Foundation of China(11175257)Key Laboratory of Neutron Detection and Electronics of Dongguan Municipality
文摘The investigation of a novel thermal neutron detector is developed to fulfill the requirements of the high intensity power diffractometer （HIPD） at the Chinese Spallation Neutron Source （CSNS）. It consists of two layers of 6LiF/ZnS（Ag） scintillators, two layers of crossed WLSF arrays, several multi-anode photo multiplier tubes （MA-PMT）, and the matching readout electronics. The neutron detection efficiency of the scintilltors, the light transportation ability of the WLSF, and the spatial linearity of the readout electronics are measured and discussed in this paper. It shows that the sandwich structure and the compact readout electronics could fulfill the needs of the HIPD. A prototype with a 10 cm×10 cm sensitive area has been constructed to further study the characteristics of the neutron scintillator detector.
