Azimuthal Asymmetry of Pion-Meson Emission around the Projectile and Target Sides in Au+Au Collision at 1A GeV
WANG Ting-Ting1,2, LU Ming1,2, MA Yu-Gang1**, FANG De-Qing1, WANG Shan-Shan1,3, ZHANG Guo-Qiang1
1Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 2University of Chinese Academy of Sciences, Beijing 100049 3Institute of Particle and Nuclear Physics, Henan Normal University, Xinxiang 453007
The ratio of the number of emitted pions from the target side to that from the projectile side at target rapidity within the reaction plane is investigated for the study of the pion dynamics with an isospin-dependent quantum molecular dynamic model. The results show that high-energy pions are emitted preferentially towards the target side and, therefore, they are freezed out at the early stage of the collision. By contrast, low-energy pions are emitted predominantly in the opposite direction, which means that they are emitted in a later stage. This argument is based on the shadowing effect caused by the interaction of pions with the spectator matter in peripheral collisions at target or projectile rapidities. This phenomenon disappears in the central collision or at midrapidity due to the weaker shadowing effect. The calculated ratios are also compared with the experimental data.
(Monte Carlo simulations (including hadron and parton cascades and string breaking models))
引用本文:
. [J]. 中国物理快报, 2015, 32(06): 62501-062501.
WANG Ting-Ting, LU Ming, MA Yu-Gang, FANG De-Qing, WANG Shan-Shan, ZHANG Guo-Qiang. Azimuthal Asymmetry of Pion-Meson Emission around the Projectile and Target Sides in Au+Au Collision at 1A GeV. Chin. Phys. Lett., 2015, 32(06): 62501-062501.