In heavy ion collision, the event plane is a key parameter defined as the plane composted by the impact parameter b and beam axis z, It is a crucial reference for various observables, which focus on the initial spatia...In heavy ion collision, the event plane is a key parameter defined as the plane composted by the impact parameter b and beam axis z, It is a crucial reference for various observables, which focus on the initial spatial anisotropy of the overlap region in heavy ion collision. We notice that in some recent heavy ion collision experiments, due to potentially inefficient or even the invalidity of experimental facilities, the reconstructed event plane, which is used in elliptic flow study, may be biased towards a non-flat distribution. In this study, we develop a toy model for fast estimation of the bias effect and its influence on the elliptic flow. The possible azimuthal bias of the detector is firstly studied by varying the part of its azimuthal information. We also study on the limit acceptance of the detector, which will be used to measure the particle of interest in an elliptic flow. The outcomes are presented by comparing the flow study results with or without the non-flat effect on the event plane.展开更多
We study the rapidity losses in central heavy-ion collisions from ACS to RHIC encrgolcs with the mean rapidity determined from the projectile net-baryon distribution after collisions. The projectile net-baryon distrib...We study the rapidity losses in central heavy-ion collisions from ACS to RHIC encrgolcs with the mean rapidity determined from the projectile net-baryon distribution after collisions. The projectile net-baryon distribution in the full rapidity range is obtained by phenomenologically removing the target contribution at the forward rapidity region from the experimental net-baryon measurements and taking into account the projectile contribution in the backward rapidity region. Based on the full projectile net-baryon distributions, calculations show that the rapidity loss stops increasing from the SPS top energy to RHIC energies, indicating that baryon transport does not depend strongly on energy at high energies.展开更多
基金Supported by the Doctoral Research Fund of Guizhou Normal University, the National Natural Science Foundation of China under Grant Nos 11305040, 10635020, 10635020, 10975062, 11020101060 and 10875051, the Program of Introducing Talents of Discipline to Universities under Grant No B08033, and the China Scholarship Council under Grant No 2011677012.
文摘In heavy ion collision, the event plane is a key parameter defined as the plane composted by the impact parameter b and beam axis z, It is a crucial reference for various observables, which focus on the initial spatial anisotropy of the overlap region in heavy ion collision. We notice that in some recent heavy ion collision experiments, due to potentially inefficient or even the invalidity of experimental facilities, the reconstructed event plane, which is used in elliptic flow study, may be biased towards a non-flat distribution. In this study, we develop a toy model for fast estimation of the bias effect and its influence on the elliptic flow. The possible azimuthal bias of the detector is firstly studied by varying the part of its azimuthal information. We also study on the limit acceptance of the detector, which will be used to measure the particle of interest in an elliptic flow. The outcomes are presented by comparing the flow study results with or without the non-flat effect on the event plane.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10975061, 10875051 and 10635020, the National Key Basic Research Program of China under Grant No 2008CB317106, and the Ministry of Education of China under Grant Nos 306022 and IRT0624.
文摘We study the rapidity losses in central heavy-ion collisions from ACS to RHIC encrgolcs with the mean rapidity determined from the projectile net-baryon distribution after collisions. The projectile net-baryon distribution in the full rapidity range is obtained by phenomenologically removing the target contribution at the forward rapidity region from the experimental net-baryon measurements and taking into account the projectile contribution in the backward rapidity region. Based on the full projectile net-baryon distributions, calculations show that the rapidity loss stops increasing from the SPS top energy to RHIC energies, indicating that baryon transport does not depend strongly on energy at high energies.
