Some Issues On The HBT Puzzle In Relativistic Heavy Ion Collisions

In 1956, in a pioneering experiment, Hanbury-Brown and Twiss use the connection of two photons measured angular diameter of the stars, At the same time when one photon was detected by a detector, the probability of another photon was also detected response to the distance of their detectors, the connection relies on the angular diameter of the emission source. For the connection associated with the measurement of intensity of the two particles, such intervention study was also called the intensity of the intervention study. In many high-energy nuclear collisions experiment, people measure the connection of two identical particles intensity correlation in the space of energy and momentum to get the information of source. This kind of the connection is call Hanbury-Brown-Twiss (HBT) effect.Before the study of HBT model, it is necessary to introduce the background knowledge of hydrodynamic model. In the 1950s, the Landau first presented with a hydrodynamic model to study the high energy collision of strong interaction material, because the conception is simple and beauty, the hydrodynamic model was widely used in high energy collision, and it fit experiment very well. The paper includes the whole process of the establishment of hydrodynamic model, which include hydrodynamic prerequisites, initialization, hydrodynamic equations of motion, the properties of the hydrodynamic model and decoupling of freeze-out. The decoupling of freeze-out also marks the end of the hydrodynamic evolution. We will introduce the distribution model of particles Bolzmann distribution and Tsallis statistical model which are also the basic model for our work to study the distribution of particles.Then we discuss the global transverse observables, it closely related with HBT model, because the particles spectrum is the basis of HBT model. In this section we will discuss transverse observables, included transverse particles spectrum. We will see it fit well with the measures of the experiment, even in the centrality of 60-92% periphery collision and in the condition of low transverse momentum, it also fit very well. Then we talk about particle multiplicity and mean transverse momentum and so on.Then we began to discuss HBT model, the paper involved derivation of HBT model. To pions for example, from the wave function, using Feynman integral to get the wave functions of identical particles, which will overlay in the detectors. We can get the correlation function in two conditions, complete chaos or complete coherent source. Particular in the complete coherent source, the correlation function is normalized, so the probability we detect one pions is independence of another pions, it is also mean there have no correlation in the momentum of two particles.Then in the condition of chaos we begin to discuss the HBT correlation, our creative of paper is discuss Bolzmann model and Tsallis model, and use two model fit Gaussian distribution function, to get the information of source, and contrast with the experiment. We also get HBT radius and HBT puzzle from two distribution model.