质子打靶时刻T0作为中国散裂中子源(Chinese Spallation Neutron Source,CSNS)多物理谱仪的初始触发信号,其高准确性和高稳定性是谱仪高效运行的前提和基础。在实验物理和工业控制系统(Experimental Physics and Industrial Control Sys...质子打靶时刻T0作为中国散裂中子源(Chinese Spallation Neutron Source,CSNS)多物理谱仪的初始触发信号,其高准确性和高稳定性是谱仪高效运行的前提和基础。在实验物理和工业控制系统(Experimental Physics and Industrial Control System,EPICS)平台上开发了一套CSNS多物理谱仪T0信号触发监测系统。T0信号接入T0扇出器标记高精度时间戳,采用高吞吐量的分布式发布订阅消息系统Kafka来实现大数据流量的削峰和异步通信。监测数据作为过程变量(Process Variable,PV)上传EPICS,利用Open-Falcon监控系统和可视化工具Grafana实现对数据的监测与可视化。该系统可以对T0信号的频率和T0在扇出与传输过程中的时间延迟进行实时监测,从而保证CSNS多物理谱仪的正常运行。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
文摘质子打靶时刻T0作为中国散裂中子源(Chinese Spallation Neutron Source,CSNS)多物理谱仪的初始触发信号,其高准确性和高稳定性是谱仪高效运行的前提和基础。在实验物理和工业控制系统(Experimental Physics and Industrial Control System,EPICS)平台上开发了一套CSNS多物理谱仪T0信号触发监测系统。T0信号接入T0扇出器标记高精度时间戳,采用高吞吐量的分布式发布订阅消息系统Kafka来实现大数据流量的削峰和异步通信。监测数据作为过程变量(Process Variable,PV)上传EPICS,利用Open-Falcon监控系统和可视化工具Grafana实现对数据的监测与可视化。该系统可以对T0信号的频率和T0在扇出与传输过程中的时间延迟进行实时监测,从而保证CSNS多物理谱仪的正常运行。
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.
