CsI晶体粒子别性能研究-物理学 粒子物理与原子核物理专业毕业论文.docx

兰州大学硕士学位论文Abstract 兰州大学硕士学位论文 Abstract In study of the experimental nuclear physics and the nuclear technology,the radiation what we measured usually accompany啊m substantial unexpected radiations．For instance，the neutron field always accompany淅tll substantial gamma rays。In the study of(n，x)reaction， many kinds of charged particle Call be produced．Therefore，the particle identification(PID) technology must be applied in order to get the correct result． In this work,three methods are applied to study the PID of a CsI(T1)crystal carefully．As is well known,in many scintillation crystals，the decay of the light emitted by the charged particles consists of two components of the signal that are the fast and slow ones．Their intensifies are relevant to ionizationnsity and therefore depend on the mass,charge and energy of the detected particles．Based on the pulse-shape-discrimination(PSD)of the Csl(T1)crystal，The zero-crossing method，the rise time method and the charge comparison method ale used to realize the good PID for口、7 and p particles． During the experiment,the base of me PMT and the electronic parameters were optimized． Then the signals were recorded by the CAMAC data acquisition system、^，inl list mode．The data were analyzed in detail with Krnax soRware package and good PID had been obta／ned．Among the three different methods，the zero-crossing method shows the best resuR because it call reach a lowest energy limit which can separate light charged particles well．The rise time method and the charge comparison method have similar capability for the PID． In many nuclear physics experiments，substantial interference radiations call be excluded only 900d PID could be obtained．The CsI(T1)detectors developed in this work will be used for 旭x)reaction research in the future．Therefore，the study of the PID of the CsI(T1)crystal is very important and meaningful． Keywords： CsI(T1)detector、particle—shape·discrimination、particle identification、the 7_鹭ro·crossing point method、the rise tim