Research On Test System Of Position-sensitive Optoelectronic Detectors Performance

Photomultiplier tube(PMT)and silicon photomultiplier tube(Si PM)are optoelectronic detectors,widely used in the fields of nuclear physics and high energy physics.With the continuous optimization and improvement of the performance of optoelectronic detectors,the function and performance requirements of the test system are correspondingly improved.In routine experiments,the single-channel signal output by the optoelectronic detectors is usually tested to complete the calibration of its performance.For the array type multi-anode photomultiplier tube(MAPMT)with position resolution function,the single-channel test method will introduce a series of measurement errors,even exceeding the system error,resulting in unreliable measurement results.At the same time,considering the performance calibration requirements of optoelectronic detectors under beam current and special places,a test system that obtain physical information such as charge,time,pulse shape discrimination and so on at the same time,portable,and meets multiple simultaneous measurements will be able to complete the performance calibration of optoelectronic detectors more efficiently.This article has thoroughly studied the two waveform sampling test systems of multi-channel desktop digitizer(DT)and multi-channel digital pulse analyzer(DPP),finished the calibration of position-sensitive optoelectronic detectors and solved the problem of the performance test requirements of position-sensitive optoelectronic detectors in different places effectively.At the same time,this will also provide an effective test method for the development of ultra-fast position-sensitive multi-anode photomultiplier tubes(FPMT)made in China.For DT,because it does not have the corresponding control software,according to its working principle and the testing requirements of conventional optoelectronic detectors,the software development is completed based on the Lab VIEW programming language.The software developed can realize functions such as waveform acquisition,data storage,multi-channel data acquisition,online integration(QDC)and other functions in multiple trigger working modes.Based on the 16-channel light source drive circuit and Si PM,the DT and the development software were jointly debugged and tested.In addition,the waveform information of the output signal of the light source driving circuit is acquired and the multiphoton spectrum test of Si PM is realized.In the research process of the DPP test system,the performance of the 20-inch microchannel plate photomultiplier tube(MCP-PMT)and Si PM was tested using DPP and a conventional test system.Under these two test systems,the charge spectrum and transit time dispersion(TTS)tests of 20-inch MCP-PMT and Si PM have been realized,and the performance test results of optoelectronic devices obtained under the two test systems are basically the same.At the same time,the calibration of the least significant bit(LSB)of DPP is completed.Finally,based on the DPP test system,the calibration of the high voltage gain curve and anode performance(peak-to-valley ratio,gain,and transit time dispersion)of MAPMT is completed.At the same time,based on DPP and DT,CLYC crystal and GAGG combined crystal are respectively coupled with optoelectronic devices to realize pulse shape discrimination(PSD)under radioactive source and beam current.