Directed flow of charged particles within idealized viscous hydrodynamics at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider
Ze-Fang Jiang (Institute of Particle Physics, Central China Normal University, Wuhan 430079, China, Department of Physics and Electronic-Information Engineering, Hubei Engineering University, Xiaogan 432000, China, Key Laboratory of Quark and Lepton Physics, Ministry of Education (MOE), Wuhan 430079, China); C.B. Yang (Institute of Particle Physics, Central China Normal University, Wuhan 430079, China, Key Laboratory of Quark and Lepton Physics, Ministry of Education (MOE), Wuhan 430079, China); Qi Peng (Department of Physics and Electronic-Information Engineering, Hubei Engineering University, Xiaogan 432000, China)
Following the Bożek-Wyskiel parametrization tilted initial condition, an alternative way to construct a longitudinal tilted fireball based on the Glauber collision geometry is presented. This longitudinal tilted initial condition combined with the Ideal-CLVisc hydrodynamic model, a nonvanishing directed flow coefficient in a wide range is observed. After comparing the model's results with experimentally observed data of directed flow coefficient from collisions at RHIC energy to and collisions at the LHC energy. One finds that directed flow measurements in heavy-ion collisions can set strong constraints on the imbalance of forward and backward incoming nuclei and on the magnitude asymmetry of pressure gradients along the direction.
