Large Scale Signal Readout Method For Position Sensitive Neutron Detection Experiments

In the past several years,the application of neutron scattering technology is becoming more and more important in the analysis of many condensed matters and the development of advanced materials.The precision experiments involved in such analyses and development often require large detector systems.In particular,the instruments at CSNS(China Spallation Neutron Source),CARR(China Advanced Research Reactor)and CMRR(China Mi-anyang Research Reactor)ect require large detector systems,which can cover very large solid angles,have a high pixel resolution and many time-of-flight(TOF)channels.The position-sensitive detectors adopted by these large detector systems always need high counting rate,high detection efficiency,high sensitive area,good n/y rejection ratio,good location resolution,etc.Also taking into account that MWPC detector has a lot of applications in China,for example the neutron multi-function reflectometer,neutron small angle scattering spectrometer at CSNS and the neutron stress spectrometer,neutron reflectance spectrometer,neutron three axis spectrometer,neutron small angle scattering spectrometer at the CMRR all use MWPC detector.To summarise,in the field of neutron scattering research in China,the lager area MWPC detector will occupy a very important position:in the future.Also,with the rapid development of neutron source,as an important nondestructive testing technique,neutron radiography has been applied to many areas.Due to good spatial resolution,high neutron detection efficiency,neutron sensitive microchannel plate(MCP)and neutron imaging detectors based on MCP have played an important role among various neutron imaging facilities.Therefore,research on readout method of neutron imaging detectors based on MCP is very meaningful.Because of the total number of readout electronics channels of the lager area MWPC detector and neutron imaging detectors based on MCP in large detector systems is quite large,which often more than 100 channnels.We put forward a multiplex readout method to reduce the scale of readout electronics.By controlling the switch array,the thousands of signals can read out one by one,to reduce the use of ADC(analog to digital converter).Also the dead time of the readout sysytem can be controlled by using the switch which has small value of Ton/Toff(the delay time of switch from breaking to closing/the delay time of switch from closing to breaking)and using more amounts of ADC.