Data Acquisition System’s GPS Timer Of Tibet Muon Detector

Cosmic ray physics is a youthful subject, and it provides the direct swatch forpeople’s studying high-energy particles. Cosmic ray’s energy spectrum approximatelyfollows a power law with negative index.Energy spectrum appears a turn called kneeat4PeV. The index changes from-2.7to-3.1.It is very important significant to studythe knee, because the change of energy spectrum is related to origin, acceleration andpropagation mechanism of the primary cosmic ray.Yangbajing international observatory of cosmic ray is located at the yangbajingtown,in Lhasa,4300m above sea level,being now at the maximum of air showerdevelopment that cosmic ray of the knee.Yangbajing has advantaged condition ofgeography. Sino-Japanese cooperation AS experiment has run stably almost for20years since1991.Because it has no capability to differentiate the component ofprimary cosmic ray.It can not eliminate the background of cosmic ray when studyingγ astronomy. A project has been built five underground Muon Detector Array.Chinese independent design and construction one of those. Muon detectors and ground arrayscarried mixture detection. The GPS Timer can timing the trigger signal to incorporate the date ofMoun Detector Array and ground arrays. The work of the Master’s thesis is making the GPSTimer.The first chapter of the paper introduces the basic knowledge of cosmic rayparticles and extensive air shower. analyzing the necessity of building MD-array byintroducing the ASγexperiment fundamental state,In the second chapter, design principle, project present state, and data acquisitionsystem of Tibet MD-A array builded by Chinese are introduced concretely. In thischapter, asserting a claim and giving contrivance of GPS timer.The third chapter introduces the data acquisition modules of GPS timer andmain chips in modules, and the focal points and difficulties that should be taken intoconsideration during making circuit board are described in detail, the function ofaspect is mainly about the describing FPGA chip programming.The fourth chapter describes GPS timing data transmission module. The microcontroller embedded TCP/IP protocol to achieve network transmission. In thischapter I described the data transfer module’s hardware circuit and introduction toTCP/IP protocol. Described how to use agreement in the data transfer module.The fifth chapter is part of the circuit board test. We can give the board thevarious indicators in those text and advantages and disadvantages of the GPS Timer.The sixth chapter is conclusion of the paper.