| Time projection chamber(TPC)is a widely used detector.It has the ability of high precision 3D track detection,and it could give the momentum and energy loss information of particles,which is helpful for the identification of particle types.TPC based on GEM is developed in recent years,compared with the traditional TPC based on multi structure,it has made great progress in the counting rate,positive ion feedback,position resolution and other aspects,it is a hot research topic in the world in the field of gas detector.In order to study the performance of GEM-TPC systematically,in this paper,three aspects are discussed including particle transmission in GEM detector,field cage field optimization,and GEM-TPC performance test.In the first part,mainly study the effects of drift filed,transmission field,induction field and the voltage distribution in different GEM film on particle transport in detector.Compared with the experimental,the two results are in good agreement.According to the law obtained,we can choose the right working conditions in the face of different needs.In the second part,the source of the electric field distortion in the drift region is analyzed,the influence of various variables on the electric field in drift region is calculated in the two models of electrode ring cage and printed circuit board field cage,measured the importance of each variable,and two optimal design schemes of field cage are proposed.Most of the optimization schemes based on the calculation have been verified in the experiment.According to the above results of the two part,we set up a 10×10cm2 GEM-TPC in the laboratory,the maximum drift distance is 15cm。In the third part,we mainly introduce the formation process and test results of GEM detector,the laser calibration system and the resolution of Z position resolution in TPC,the experimental results show that the position resolution of the GEM-TPC is about 100μm in the direction of Z. |
