The On-orbit Simulation And Alignment Of The DArk Matter Particle Explorer

As an unsolved mystery of human scientific research,dark matter is a hot spot in modern astronomy.Numerous scientists have devoted their whole life to explore the nature of dark matter.DArk Matter Particle Explore(DAMPE)is the first astronomical satellite in China.It is one of the satellite-based particle detectors with high energy res-olution and wide energy band.The main scientific goal of the DAMPE is to accurately measure the cosmic ray electrons,protons and nuclides,as well as gamma-rays,to in-directly search for possible signals of dark matter.Due to its high energy resolution,the DAMPE has some advantages in indirect detection of dark matter particles,especially in ?-ray line spectrum search.The author is mainly responsible for the development and maintenance of off-line data processing software,the research of detector related simulation and reconstruction algorithm,and the analysis and calibration using ?-ray data.This paper introduces some related research progress and results in the DAMPE collaboration.The first chapter introduces the research background of data analysis work about the DAMPE.Firstly,I describe the existence evidence,related theoretical model and detection method of dark matter,as well as the DAMPE,whose main scientific objective is indirect detection for dark matter.And then I briefly introduce the design principle and related performance of the payload of DAMPE.In orbit operation,the calibration data analysis of the instrument not only shows the good performance of the detector,but also is the basis of this paper.The second chapter introduces the off-line data processing software and the de-tector simulation based on this software.The offline data processing software is the key to coordinate the data analysis of the whole cooperation.I participated in the de-velopment of the offline data processing software framework during my undergraduate degree.After the satellite was in orbit,I have been independently responsible for the follow-up maintenance and optimization.In the analysis of proton spectrum,I analyzed the simulation data of FLUKA and GEANT4.According to the comparison of hadron shower process in the BGO calorimeter,it is estimated that the overall systematic er-ror of the hadron model uncertainty in the DAMPE measurement of proton spectrum is about 10%.In the third chapter,I introduce a set of program for the simulation of DAMPE ?-ray survey independently developed by me according to the previous detector simulation and the relevant experience of other similar detectors in the world.This simulation program plays an important role in ?-ray astronomy research of DAMPE,for it can accurately simulate the specific process of ?-ray observation by DAMPE.In this chapter,the principle of simulated stochastic process and the implementation of the algorithm are presented in detail,and the related verification results are also given.At the same time,it can be cross validated with other independent ?-ray analysis programs and observation data.In Chapter 4,we present a maximum likelihood estimation(MLE)method to mea-sure the angle deviation between the payload and the satellite platform of about 0.15 CI RC.Meanwhile,the simulation progral described in Chapter 3 is used to validate the alignment method.This alignment effectively improves the ?-ray measurement ac-curacy of DAMPE and lays a good foundation for subsequent physical results.The last chapter is the summary of the whole paper and the prospect of future work.