Speaker：徐浩洁

Title: Gauge the v2-indcued backgournd on chiral magnetic effect search

Abstract:

  Due to the topology of  QCD vacuum, a strong magnetic field can lead to an electric current, or charge separation (cs) in heavy ion collisions (HIC), this is the so-called chiral magnetic effect (CME). The cs has been observed in HIC experiments by azimuthal correlator Δ γ , but was contaminated by a major background from another azimuthal correlator v2. The most popular way to control the background is the isobaric 4496Ru+4496Ru and 4096Zr+4096Zr collisions, which have been proposed and planned at RHIC in 2018. In this talk, however, it will been firstly shown that the expectations on isobaric collisions may not hold as originally anticipated due to large uncertainties from isobaric nuclear densities. Moreover, a new method is proposed to even better gauge background contributions in a single nucleus-nucleus collision. The new method is based on the opposite behavior of fluctuation detail for magnetic field and v2 in a single collision, thus bear minimal theoretical and experimental uncertainties. Finally, the method is applied to the existing data at RHIC, the outcome of which is discussed.

References：arXiv:1710.03086, arXiv:1710.07265

2017-12-08, 3:00PM，物理学院322