Charge-dependent flow and the search for the chiral magnetic wave in Pb-Pb collisions at √sNN = 2.76 TeV
Charge-dependent flow and the search for the chiral magnetic wave in Pb-Pb collisions at √sNN = 2.76 TeV
复制标题
DOI：
10.1103/physrevc.93.044903
复制
发表时间：
2015-12
影响因子：
3.1
通讯作者：
Alice Collaboration
中科院分区：
文献类型：
--
作者：
Alice Collaboration
本文报道了在欧洲核子研究中心（CERN）大型强子对撞机（LHC）上利用新型三粒子相关器和ALICE测量铅铅碰撞中的电荷相关流，并讨论了其对重离子碰撞中局部宇称破缺和手征磁波（CMW）观测的影响。电荷依赖流报告为不同的碰撞中心作为事件电荷不对称的函数。虽然我们的结果是在定性协议与期望的基础上的CMW，在高次谐波相关性中观察到的非零信号表明可能显着的背景贡献。我们还提出了一个差分相关的结果，其中的正电荷和负电荷的流量报告作为粒子的平均电荷和它们的赝快度分离的函数。我们认为，这种差分相关器更适合区分预期由于CMW和背景效应，如局部电荷守恒耦合强径向和各向异性流的正电荷和负电荷的差异。
We report on measurements of a charge-dependent flow using a novel three-particle correlator with ALICE in Pb-Pb collisions at the CERN Large Hadron Collider (LHC), and discuss the implications for observation of local parity violation and the chiral magnetic wave (CMW) in heavy-ion collisions. Charge-dependent flow is reported for different collision centralities as a function of the event charge asymmetry. While our results are in qualitative agreement with expectations based on the CMW, the nonzero signal observed in higher harmonics correlations indicates a possible significant background contribution. We also present results on a differential correlator, where the flow of positive and negative charges is reported as a function of the mean charge of the particles and their pseudorapidity separation. We argue that this differential correlator is better suited to distinguish the differences in positive and negative charges expected due to the CMW and the background effects, such as local charge conservation coupled with strong radial and anisotropic flow.