Title: Evidence of the Chiral Magnetic Effect in Au+Au Collisions at √sNN=200 GeV at the Relativistic Heavy Ion Collider

PAs: Yicheng Feng, Jie Zhao, Haojie Xu, Fuqiang Wang

Targeted journal: PRL

Abstract: 
Vacuum fluctuations of the topological gluon field in quantum chromodynamics will produce a chirality imbalance of quarks and, in a strong magnetic field, a subsequent electric current, a phenomenon called the chiral magnetic effect (CME). We report an evidence of the CME in Au+Au collisions at nucleon-nucleon center-of-mass energy of √sNN=200 GeV at BNL's Relativistic Heavy Ion Collider by a charge-dependent azimuthal correlator after removal of  flow-induced backgrounds and nonflow contamination. The significance of the CME signal is  3.4 standard deviation.

Conclusion: 
After eliminating flow-induced backgrounds and nonflow contamination, we report an evidence of the CME in 20--50\% centrality Au+Au collisions at $\snn=200$~GeV with a signal fraction of $\fcme=(25±7±2)% in the measured inclusive Δγ, a 3.4 standard deviation away from, or a 3.4×10^-4 probability to be a fluctuation of, a null signal.

Status: 
2024/08/21, FCV meeting, paper proposal

Paper draft: 

Analysis note: 

CVS: 

Previous presentations:
2024/08/14, FCV meeting, drupal.star.bnl.gov/STAR/system/files/Fcme20240812_v2.pdf 
2024/08/09, CME-fg meeting, drupal.star.bnl.gov/STAR/system/files/Fcme20240807_v3.pdf 
2024/07/24, FCV meeting, drupal.star.bnl.gov/STAR/system/files/FlowDecor20240721.pdf 
2024/05/15, CME-fg meeting, drupal.star.bnl.gov/STAR/system/files/Fcme20240514_v4.pdf 
2024/04/02, FCV meeting, drupal.star.bnl.gov/STAR/system/files/Fcme20240402.pdf 

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