1.School of Science, Huzhou University, Huzhou 313000, China
2.Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
Corresponding author, fqwang@zjhu.edu.cn
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Fu-Qiang Wang, Jie Zhao. Search for the chiral magnetic effect in heavy ion collisions. [J]. Nuclear Science and Techniques 29(12):179(2018)
Fu-Qiang Wang, Jie Zhao. Search for the chiral magnetic effect in heavy ion collisions. [J]. Nuclear Science and Techniques 29(12):179(2018) DOI: 10.1007/s41365-018-0520-z.
Quark interactions with topological gluon fields in quantum chromodynamics can yield local ,𝒫, and ,𝒞𝒫, violations that could explain the matter–antimatter asymmetry in our universe. Effects of ,𝒫, and ,𝒞𝒫, violations can lead to charge separation under a strong magnetic field, a phenomenon called the chiral magnetic effect (CME). Early measurements of the CME-induced charge separation in heavy ion collisions are dominated by physics backgrounds. This report discusses the recent innovative efforts in eliminating those backgrounds, namely, by event-shape engineering, invariant-mass dependence, and reaction and participant plane comparison. The background-free CME measurements using these novel methods are presented.
Heavy ion collisionsChiral magnetic effectAzimuthal correlatorFlow backgroundInvariant massReaction planeParticipant plane
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