System design for precise digitization and readout of the CSNS-WNS BaF2 spectrometer  

作　　者：张德良 曹平 王奇 何兵 张雅希 齐心成 余滔 安琪 

机构地区：[1]State Key Laboratory of Particle Detection and Electronics, University of Science and Technology of China, Hefei 230026, China [2]Department of Modern Physics, University of Science and Technology of China, Hefei 230026, China [3]School of Nuclear Science and Technology, University of Science and Technology of China, Hefei 230027, China

出　　处：《Chinese Physics C》2017年第2期159-165,共7页中国物理C（英文版）

基　　金：Supported by National Research and Development plan(2016YFA0401602);NSAF(U1530111)

摘　　要：The BaF2 （barium fluoride） spectrometer is one of the experiment facilities at the CSNS-WNS（White Neutron Source at China Spallation Neutron Source）, currently under construction. It is designed to precisely measure the（n, γ） cross section, with 92 crystal elements and complete 4π steradian coverage. In order to improve the precision of measurement, in this paper, a new precise digitization and readout method is proposed. Waveform digitizing with 1 GSps sampling rate and 12-bit resolution is used to precisely capture the detector signal. To solve the problem of massive data readout and processing, the readout electronics is designed as a distributed architecture with 4 PXIe crates. The digitized signal is concentrated to the PXIe crate controller through a PCIe bus on the backplane and transmitted to the data acquisition system over gigabit Ethernet in parallel. Besides, the clock and trigger can be fanned out synchronously to every electronic channel over a high-precision distribution network. Test results show that the prototype of the readout electronics can achieve good performance and meet the requirements of the CSNS-WNS BaF2 spectrometer.The BaF2 （barium fluoride） spectrometer is one of the experiment facilities at the CSNS-WNS（White Neutron Source at China Spallation Neutron Source）, currently under construction. It is designed to precisely measure the（n, γ） cross section, with 92 crystal elements and complete 4π steradian coverage. In order to improve the precision of measurement, in this paper, a new precise digitization and readout method is proposed. Waveform digitizing with 1 GSps sampling rate and 12-bit resolution is used to precisely capture the detector signal. To solve the problem of massive data readout and processing, the readout electronics is designed as a distributed architecture with 4 PXIe crates. The digitized signal is concentrated to the PXIe crate controller through a PCIe bus on the backplane and transmitted to the data acquisition system over gigabit Ethernet in parallel. Besides, the clock and trigger can be fanned out synchronously to every electronic channel over a high-precision distribution network. Test results show that the prototype of the readout electronics can achieve good performance and meet the requirements of the CSNS-WNS BaF2 spectrometer.

关 键 词：CSNS-WNS BaF2 spectrometer readout electronics waveform digitizing clock and trigger network 

分 类 号：TH744.1[机械工程—光学工程] O571.5[机械工程—仪器科学与技术]