Readout electronics of a prototype time-of-flight ion composition analyzer for space plasma  

作　　者：Di Yang Zhe Cao Xin-Jun Hao Yi-Ren Li Shu-Bin Liu Chang-Qing Feng Qi An 

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]Division of Space Physics, University of Science and Technology of China, Hefei 230026, China [4]CAS Key Laboratory of Geospace Environment,Hefei 230026, China

出　　处：《Nuclear Science and Techniques》2018年第4期98-107,共10页核技术（英文）

基　　金：supported by the National Key Scientific Instrument and Equipment Development Projects of the National Natural Science Foundation of China(No.41327802);China Mars Project

摘　　要：Readout electronics is developed for a prototype time-of-flight(TOF) ion composition spectrometer for in situ measurement of the mass/charge distributions of major ion species from 200 to 100 ke V/e in space plasma.By utilizing a constant fraction discriminator(CFD) and time-to-digital converter(TDC), challenging dynamic range measurements were performed with high time resolution and event rates. CFD was employed to discriminate the TOF signals from the micro-channel plate and channel electron multipliers. TDC based on the combination of counter and OR-gate delay chain was designed in a highreliability flash field programmable gate array. Owing to the non-uniformity of the delay chain, a correction algorithm based on integral nonlinearity compensation was implemented to reduce the time uncertainty. The test results showed that the electronics achieved a low timingerror of < 200 ps in the input range from 35 to 500 m V for the CFD, and a time resolution of ～550 ps with time uncertainty < 180 ps after correction and a time range of6.4 ls for the TDC. The TOF spectrum from an electron beam experiment of the impacting N_2 gas further indicated the good performance of this readout electronic.Readout electronics is developed for a prototype time-of-flight(TOF) ion composition spectrometer for in situ measurement of the mass/charge distributions of major ion species from 200 to 100 ke V/e in space plasma.By utilizing a constant fraction discriminator(CFD) and time-to-digital converter(TDC), challenging dynamic range measurements were performed with high time resolution and event rates. CFD was employed to discriminate the TOF signals from the micro-channel plate and channel electron multipliers. TDC based on the combination of counter and OR-gate delay chain was designed in a highreliability flash field programmable gate array. Owing to the non-uniformity of the delay chain, a correction algorithm based on integral nonlinearity compensation was implemented to reduce the time uncertainty. The test results showed that the electronics achieved a low timingerror of < 200 ps in the input range from 35 to 500 m V for the CFD, and a time resolution of ～550 ps with time uncertainty < 180 ps after correction and a time range of6.4 ls for the TDC. The TOF spectrum from an electron beam experiment of the impacting N_2 gas further indicated the good performance of this readout electronic.

关 键 词：Space plasma Ion composition ANALYZER READOUT electronics Constant FRACTION DISCRIMINATOR Time-to-digital converter 

分 类 号：TL[核科学技术]