Jet And Hadron Production Based On The Linear Boltzmann Transport Model

Modern physics studies suggest that the product of the early stage of the big bang may be the quark gluon plasma(QGP).The research of quark gluon plasma by the scholars in the field of physics is not only of great significance,but also will further deepen the understanding of the current stage of physics,ranging from the evolution of the universe,the formation of stars,to the four basic interactions between the microstructure of matter and matter.Because quark gluon plasma is a new state of matter composed of uncoupled quarks and gluons,physicists' research on QGP is not only to explore the early evolution of the universe,but also to help understand the strong interaction,namely quantum chromodynamics(QCD).At present,quark gluon plasma(QGP)is produced in the laboratory through the high temperature and high density provided by relativistic heavy ion collision,This is the case in the extreme relativistic heavy ion collision experiments conducted on the Relativistic Heavy Ion Collider(RHIC)of the Brookhaven National Laboratory(BNL)and the Large Hadron Collider(LHC)of the European Nuclear Center(CERN).With the continuous efforts of several generations of physicists,researchers have finally deduced the existence of QGP,a new form of matter,based on the prediction of basic physical theory and a large number of heavy ion experimental data.The jet quenching in the large transverse momentum region and the collective flow in the small momentum region of the final hadron are important evidences for the existence of QGP.There are many methods to study the properties of QGP in relativistic heavy ion collisions.Two important approaches are jet quenching and the final hadron collective flow.In the extreme relativistic heavy ion collision experiment,QGP,a quark matter,only exists in a very short time interval in the early stage of collision,and then QGP matter will rapidly form hadronization with time evolution.Therefore,it is an important research topic in the field of high energy physics to study the generation of QGP and the properties of QGP according to the information of the final hadron produced by relativistic heavy ion collision.In this paper,the Boltzmann equation,which describes the classical transport process,is first introduced,and then a part of the sublayer Monte Carlo model,i.e.linear Boltzmann model(LBT),which is based on the Boltzmann equation,is carefully explored.The linear Boltzmann model can be used to simulate the QGP process of heavy ion collisions with large transverse momentum.In the process of light quarks passing through the QGP quark matter,it is possible to lose energy by elastic scattering with hot dense matter,and also by radiating gluons.Thus,the influence of the molecular layer of the high-energy Parton through the molecule itself at the back of QGP and as a whole jet,as well as the influence of the high-energy Parton on the hot dense matter are studied.Our study shows that the linear Boltzmann model can well simulate the process of large transverse momentum Parton passing through QGP.Whether the final observation is a single particle level,such as charged hadron or photon hadron correlation,or as a whole jet level,such as photon labeled jet,double jet and charged jet are in good agreement with the experimental data.This shows that the LBT transport model based on Boltzmann equation can effectively describe the process of light quarks passing through QGP,which greatly promotes the research work of QGP.