Dedicated 4πβ(LS)-γ(HPGe) digital coincidence system based on synchronous high-speed multichannel data acquisition  

作　　者：陈吉锋 宋克柱 柳加成 

机构地区：[1]State Key Laboratory of Particle Detection and Electronics, USTC, Hefei, 230026, China [2]Ministry of Environmental Protection of Nuclear and Radiation Safety Center, Beijing 100082, China

出　　处：《Chinese Physics C》2016年第3期109-114,共6页中国物理C（英文版）

基　　金：Supported by National Metrology Institute of China

摘　　要：A dedicated 4πβ（LS）-γ（HPGe） digital coincidence system with five acquisition channels has been developed. Three ADC acquisition channels with an acquisition resolution of 8 bits and acquisition rate of 1 GSPS are utilized to collect the signals from three PMTs which are used to detect β decay, and two acquisition channels with an acquisition resolution of 16 bits and acquisition rate of 50 MSPS are utilized to collect the signals from high-purity germanium（HPGe）, which is used to detect γ decay. In order to increase the accuracy of the coincidence system, all five acquisition channels are synchronous within 500 ps. The data collected by the five acquisition channels will be transmitted to the host PC through a PCI bus and saved as a file. Off-line software is utilized for the 4πβ（LS）-γ（HPGe） coincidence and data analysis as needed in practical applications. Tests of the system show that system can record pulse signals from 4πβ（LS）-γ（HPGe） synchronously for further coincidence calculation and the highest coincidence rate of the system is 20 K/s, which is sufficient for most applications. Compared with traditional coincidence modules like MAC3, the digital coincidence system has a higher flexibility of coincidence algorithm. In addition, due to the use of ADC, the structure of the coincidence system is simplified. This paper introduces the design of the hardware, the synchronization method and the test results of this system.A dedicated 4πβ（LS）-γ（HPGe） digital coincidence system with five acquisition channels has been developed. Three ADC acquisition channels with an acquisition resolution of 8 bits and acquisition rate of 1 GSPS are utilized to collect the signals from three PMTs which are used to detect β decay, and two acquisition channels with an acquisition resolution of 16 bits and acquisition rate of 50 MSPS are utilized to collect the signals from high-purity germanium（HPGe）, which is used to detect γ decay. In order to increase the accuracy of the coincidence system, all five acquisition channels are synchronous within 500 ps. The data collected by the five acquisition channels will be transmitted to the host PC through a PCI bus and saved as a file. Off-line software is utilized for the 4πβ（LS）-γ（HPGe） coincidence and data analysis as needed in practical applications. Tests of the system show that system can record pulse signals from 4πβ（LS）-γ（HPGe） synchronously for further coincidence calculation and the highest coincidence rate of the system is 20 K/s, which is sufficient for most applications. Compared with traditional coincidence modules like MAC3, the digital coincidence system has a higher flexibility of coincidence algorithm. In addition, due to the use of ADC, the structure of the coincidence system is simplified. This paper introduces the design of the hardware, the synchronization method and the test results of this system.

关 键 词：liquid scintillation 4πβ（LS） –γ（HPGe） coincidence system high-speed ADC 

分 类 号：TL81[核科学技术—核技术及应用]