Study Moon Shadow With ARGO-YBJ Experiment

The data of ARGO-YBJ experiment is obtained from YangBaJing International CosmicRay Observatory. It located at YangBaJing Town in Tibet. The cosmic rays hitting on themoon leads to the loss of cosmic ray flux from the direction of the moon and this is known asthe moon shadow effect. This work mainly focus on the moon shadow analysis by using datafrom ARGO experiments. The experiments data is form2009to2011.Moon shadow can be used to study the performance of the array, which includes theangular resolution,the pointing error and calibration on absolute energy scale. According tothese properties of moon shadow, the thesis is divided into six parts as followed:In Chapter I, we give brief introduction on the examined history, basic properties ofphysics and detection methods of cosmic ray.The ARGO-YBJ experiment is introduced in Chapter2. Which include brief introductionon the data acquisition system, the time calibration and the reconstructed data structure ofARGO-YBJ detector.In Chapter3, we described the analysis method in this work. The Equity-zenith anglemethod introduced the estimate of the background and the measurement of significance.Chapter4contains the basic knowledge of moon shadow, the selection of suitable dataaccording to the feature of moon shadow, and the relevant parameters.Chapter5, which is one of the main tasks in this thesis.The moon shadow is observedwith a significance of48σ, as the data sample is from2009to2011. Detectors is stable duringthis period. The angular resolution is about0.6degree. The pointing error is less than0.01degree. In addition, the absolute energy scale is calibrated by making use of the energydependent geomagnetic field effectFinally, a summary on this thesis work and a prospect on the ARGO-YBJ experimentsare presented.