Particle Ratios Study Of RQMD Model In High Energy Relativistic Heavy Ion Collisions

By using RQMD Monte Carlo generator model, we performed an investigation on the yield ratio of various particles in relativistic heavy ion collisions in high energy physics.The yield ratio of various particles, especially the relationship on the rapidity dependence, is closely related to the kinetics mechanism in high energy nuclear-nuclear collisions. It is one of the most important studying subjects in high energy nuclear-nuclear experiments. The yield of meson is correlated with the total entropy of the system. Most of the produced strange particles are k meson, the yield of anti-baryons is correlated with the production of baryons. The ratio p/p is widely used to reflect the information of the baryon transparence. Baryon transparence (or stopping) is one of the most important quantities to reflect the early stage information in the collisions. The extent of the baryon stopping can influent the overall kinetics evolvement of the collisions, the equilibrium process of the initial partons, particles productions, thermal equilibrium, chemical equilibrium,and so on. The particles ratio reflects the chemical equilibrium in the process of the rapid expansion of the system and the force of the non-elastic collisions with the decrease of the temperature of the system. It can also reflect the chemical ingredient of the system when the hadrons are freezing. So, the investigation of the yield ration of various particles is very important for the searching of the so-called new matter Quark Gluon Plasma (QGP).In order to make much more clear of the process of high energy nuclear-nuclear collisions, we use RQMD Monte Carlo model to do our analysis. By using RQMD model, we generated 2,000,000 Monte Carlo events for AuAu minimum bias collisions at sNN = 200GeV. In order to comparison, we also generated 2.000,000 dAu events at the same energy. We investigated the dependences of anti-particle to particle ratio of various normal particles on transverse momentum, rapidity and chemical potential. We found that the yield ratio of various particles did not change with transverse momentum in both AuAu collisions and dAu collisions. By the comparison of rapidity, we saw a flat rapidity distribution appeared in the sNN = 200GeV AuAu collisions, which infers that the baryon transparence is beginning in the collisions. Due to the final state particles rescattering in RQMD model, the ratio in the flat rapidity of RQMD is smaller than that of the experimental data. So, by the comparison of the experimental data with the RQMD Monte Carlo data in various energy, we concluded that the final state particles rescattering in the experimental data was decreasing in RHIC energy.Strangeness enhancement is one of the widely used signals to study the creation of QGP. The ratio k-/it is a good quantity to measure the strangeness enhancement. Recently, a measurable variable , which considered the collision energy and centrality, is introduced in order to study the gluon saturation figure in the collisions. By comparison of the figures of the relation of k-/-K and u for various experimental data, we saw a clear gluon saturation figure appeared in RHIC energy.In conclusion, by using RQMD v2.4 we generated AuAu events in various energy. By comparison of the figures of the relation of k-/K and ω both from the RQMD generator data and experimental data, we found RQMD can well reflect the gluon saturation figure which is described by the variable LJ . We point out that ω , as a experimental measurable variable, has been slightly simplified.