The revised Landau hydrodynamic model and the pseudorapidity distributions of produced charged particles in high energy heavy ion collisions

Abstract

Using the revised Landau hydrodynamic model and taking into account the effect of leading particles, we discuss the pseudorapidity distributions of produced charged particles in high energy heavy ion collisions. As usual, the leading particles here mean the particles which inherit the quantum numbers of colliding nucleons and carry off most parts of the incident energy. We argue that the rapidity distributions of leading particles have the Gaussian form with the normalization constant being equal to the number of participants. We find that the results from the hydrodynamic model alone are not consistent with the experimental data carried out by BNL-RHIC-PHOBOS Collaboration in Au + Au collisions at . Only after the contributions from leading particles are included, can the experimental measurements be described well.