Multifractal Structure Of Pseudorapidity And Azimuthal Distributions Of The Shower Particles In Au+Au Collisions At 200 A GeV

Searching for quark-gluon plasma(QGP)is one of the most important goals of high-energy heavy-ion collision experiments.However,the lifetime of the QGP produced in laboratory is very short.As the QGP expands,its temperature drops down and the hadronization of the plasma will take place at a critical temperature.In experiments only the final state particles(hadrons)can be detected.Maybe,those final state particles carry the messages about the evolution and interactions of the system.Thus,we can study the physical process of the phase transition through studying the distributions and correlations hid in the distribution of the final state particles.Especially,the study of the pseudorapidity and azimuthal distributions has some physical significance.In chapter one,we simply introduce the realization process of people about the substance structure,the QGP signals and the high-energy heavy-ion collision experiments. In the second part of this thesis,we introduce kinematics variables for the high-energy heavy-ion collision and introduce the high energy nuclear emulsion experiment.We present the psettdorapidity and azimuthal distributions of shower particles firially.In the third part of the thesis,we introduce the concept of fractal and summarize methods about the study of the final state particle distributions and their excellences and defects.Finally,we introduce the Multifractal Detrended Fluctuation Analysis in detail.In chapter four,we analyzes the multifractal structure of pseudorapidity and azimuthal distributions of shower particles in central Au+Au collisions at 200 A GeV by using the MFDFA and get the correspo.nding singularity spectra f(α).From the result we know both the singularity spectra f(α)corresponding toηandφare nonbourgeois functions ofαwhich suggest the pseudorapidity and azimuthal distributions of shower particles are all multifractals.From there we can also see that when the HSlder exponentαis getting bigger the singularity spectra f(α) are getting bigger,which means that with the increase of the singularity strengthαthe corresponding Hausdorff dimensions f(α)of the fractal subset are getting bigger. The multifractal structure in the spectra suggests that there exist correlations of all scales with comparable strength.This property may constrain model construction for high energy nuclear nuclear collisions...