相对论重离子碰撞手征电荷分离效应的研究  

Study of Chiral Charge Separation Effect in Relativistic Heavy Ion Collisions

作　　者：冯笙琴[1] 裴蕾[1] 孙飞 艾鑫[1] 钟洋[1] 殷中宝[2] 

机构地区：[1]三峡大学理学院,湖北宜昌443002 [2]华中师范大学粒子物理研究所,武汉430079

出　　处：《原子核物理评论》2017年第3期557-562,共6页Nuclear Physics Review

基　　金：国家自然科学基金资助项目(11475068;11247021);湖北省自然科学基金资助项目(2014CFB671)~~

摘　　要：相对论重离子碰撞的拓扑荷作用破坏作用平面两侧不同手征性的夸克数目的平衡,从而引起P和CP破坏特征。本工作主要分析RHIC和LHC能区的手征电荷分离作用,分析手征电荷分离随碰撞中心度、碰撞能量和核屏蔽等依赖关系。并未发现手征电荷分离效应与碰撞能量大小有非常紧密的依赖关系,但发现核屏蔽效应对手征电荷分离有重要的影响,与不考虑屏蔽效应相比,考虑屏蔽效应会使手征分离效应明显压低,由于屏蔽效应出现,使得a++(a--)的分布与a+-(a-+)分布并不对称。并且还发现手征分离效应主要发生在碰撞参量较大的周边碰撞,越接近中心碰撞,手征分离效应几乎可以忽略。The topological charge interactions in relativistic heavy ion collisions cause quark chirality imbalance, resulting in charge separation under the strong magnetic field and local P and CP violation. In this paper,the chiral charge separation at RHIC and LHC energies is systematically analyzed as functions of the collision centrality, the collision energy and the nuclear shielding factor. It is found that there is not a very close dependence of the chiral charge separation effect on the collision energies, but that has an important dependence on nuclear shielding factor. Compared with the non-shielding effect, the shielding effect can reduce the chiral separation effect obviously. Due to the shielding effect, the distribution of a＋＋（a--） and the distribution of a＋-（a-＋） are asymmetric. One also finds that chiral separation effect,which is almost negligible when more close to the central collision, occurs mainly in the peripheral collision for larger impact parameter.

关 键 词：手征磁效应 非中心碰撞 手征电荷分离 核屏蔽效应 

分 类 号：O572.23[理学—粒子物理与原子核物理]