DAMPE Offline Data Analysis Software Framework And Orbit Calibration Of BGO Ecal

Recent years,the observation in astronomy has proved the existence of dark mat-ter,which takes up about 26.8%of the universe constitutes while ordinary matter only occupies 4.9%.Currently,the knowledge on dark matter is still quite limited except for the fact that dark matter participates in gravitational interaction and perhaps weak interaction.Particle physics is a subject focused on the elementary component of matter and the study on dark matter is one of the most intriguing frontiers in particle physic-s.Currently,the most popular dark matter particle candidate is the Weakly Interact-ing Massive Particle(WIMPs),which mass about GeV.Experimental efforts to detect WIMPs include the search for products of WIMPs annihilation,including gamma rays and electrons.The Dark Matter Explorer(DAMPE)was started 2011 as one of the four satellites promoted by the Strategic Priority Research Program in Space Science.The main pur-pose of the DAMPE is to measure space high-energy electrons(including positrons)and gamma ray energy spectrum with the on-orbit detector which has a wide energy range and good energy resolution,thus searching for evidence of existence of dark mat-ter indirectly.The DAMPE satellite was launched successfully at 08:12 in 17/12/2015,which was a milestone in China' s dark matter explore projects.The DAMPE offline data analysis software framework is the key part of the sci-ence data analysis software,which serves as the foundation of the development of other modules and responsible for the sub-module management and as well as data manage-ment in the process execution.The framework is designed and mostly implemented by the author,which is designed as an object-oriented system,and has explicit abstrac-t function modules as well as fine extendibility.This dissertation presents the basic architecture,data management,and user development along with usage introductions.The simulation result does not only provide an expectation of experimental results or a comparison validation,but also provide some input parameters for some physical measurements for DAMPE,for instance,the acceptance which used for flux measure-ment.The detector simulation of BGO calorimeter is introduced in this thesis as well,which mainly consists of the description of the detector geometry and materials,the record and reconstruction of events and also how to add the electronics noise of the calorimeter,etc.The simulation has been applied for test beam successful,the test and simulation results verify that the BGO calorimeter has a resolution below 1.5%at the incidence electron energy of 800GeV.The BGO calorimeter is the only mean of energy measurement of the DAMPE.The calibration of the calorimeter,including the calibration of electronics pedestal,the calibration of the MIPs energy and the calibration of PMT dynode gains are of great im-portance in the energy reconstruction and in the simulation noise superposition method.We developed the on-orbit calibration methods for BGO ECAL and also studied the cal-ibration results in different magnetic environment.The calibration results have shown that the average noise level of the calorimeter channels is 7.05,which has a 0.2 variation from ground tests on average,the gains of the PMT dynodes are stable with a fluctuation of less than 0.8%,almost undisturbed by the geomagnetic field,a longtime monitoring on-orbit calibration result shows that the peak positions of MIPs have a dependence on temperature of-1.324%per degree which agrees with the ground thermal vacuum tests,the reconstructed energy of MIPs event from orbit data agrees well with Monte Carlo result.