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Observation of charge asymmetry dependence of pion elliptic flow and the possible chiral magnetic wave in heavy-ion collisions

Journal Article · · Physical Review Letters
 [1]
  1. AGH Univ. of Science and Technology, Cracow (Poland). et al.

We present measurements of π⁻ and π⁺ elliptic flow, v₂, at midrapidity in Au+Au collisions at √sNN = 200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV, as a function of event-by-event charge asymmetry, Ach, based on data from the STAR experiment at RHIC. We find that π⁻ (π⁺) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins at √sNN = 27 GeV and higher. At √sNN = 200 GeV, the slope of the difference of v₂ between π⁻ and π⁺ as a function of Ach exhibits a centrality dependence, which is qualitatively similar to calculations that incorporate a chiral magnetic wave effect. In addition, similar centrality dependence is also observed at lower energies.

Research Organization:
Brookhaven National Laboratory (BNL), Upton, NY (United States); University of Illinois, Chicago, IL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Nuclear Physics (NP)
Contributing Organization:
STAR Collaboration
Grant/Contract Number:
FG02-94ER40865
OSTI ID:
1213396
Alternate ID(s):
OSTI ID: 1236058
OSTI ID: 1665920
OSTI ID: 1198529
Report Number(s):
BNL--108305-2015-JA; KB0202012
Journal Information:
Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 25 Vol. 114; ISSN 0031-9007; ISSN PRLTAO
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (48)

Flow study in relativistic nuclear collisions by Fourier expansion of azimuthal particle distributions journal May 1996
HIJING 1.0: A Monte Carlo program for parton and particle production in high energy hadronic and nuclear collisions journal December 1994
Microscopic models for ultrarelativistic heavy ion collisions journal January 1998
The STAR time projection chamber: a unique tool for studying high multiplicity events at RHIC
  • Anderson, M.; Berkovitz, J.; Betts, W.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 499, Issue 2-3 https://doi.org/10.1016/S0168-9002(02)01964-2
journal March 2003
The STAR trigger
  • Bieser, F. S.; Crawford, H. J.; Engelage, J.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 499, Issue 2-3 https://doi.org/10.1016/S0168-9002(02)01974-5
journal March 2003
Topologically induced local PandCP violation in QCD×QED journal January 2010
Charge separation induced by -odd bubbles in QCD matter journal December 2007
The effects of topological charge change in heavy ion collisions: “Event by event and violation” journal May 2008
Partonic mean-field effects on matter and antimatter elliptic flows journal August 2014
Parity violation in hot QCD: Why it can happen, and how to look for it journal February 2006
Elliptic flow in the Gaussian model of eccentricity fluctuations journal January 2008
Azimuthally fluctuating magnetic field and its impacts on observables in heavy-ion collisions journal January 2013
Contributions to the event-by-event charge asymmetry dependence for the elliptic flow of π+ and π− in heavy-ion collisions journal October 2013
Final state effects on charge asymmetry of pion elliptic flow in high-energy heavy-ion collisions journal July 2014
Relativistic hadron-hadron collisions in the ultra-relativistic quantum molecular dynamics model journal September 1999
Partonic effects on anisotropic flows at RHIC journal March 2005
Anomalous hydrodynamics journal January 2006
Can baryon stopping explain the breakdown of constituent quark scaling and proposed signals of chiral magnetic waves at RHIC? journal September 2013
Methods for analyzing anisotropic flow in relativistic nuclear collisions journal September 1998
New method for measuring azimuthal distributions in nucleus-nucleus collisions journal April 2001
Partonic effects on the elliptic flow at relativistic heavy ion collisions journal February 2002
Azimuthal anisotropy in Au+Au collisions at s NN = 200 GeV journal July 2005
Effect of flow fluctuations and nonflow on elliptic flow methods journal July 2009
Remarks on possible local parity violation in heavy ion collisions journal March 2010
Observation of charge-dependent azimuthal correlations and possible local strong parity violation in heavy-ion collisions journal May 2010
Charge separation effect in relativistic heavy ion collisions journal November 2010
New method for the experimental study of topological effects in the quark-gluon plasma journal January 2011
Flow analysis with cumulants: Direct calculations journal April 2011
Constituent quark scaling violation due to baryon number transport journal October 2011
Effects of hadronic potentials on elliptic flows in relativistic heavy ion collisions journal April 2012
Hydrodynamics at large baryon densities: Understanding proton versus anti-proton v 2 and other puzzles journal October 2012
Inclusive charged hadron elliptic flow in Au + Au collisions at s N N = 7.7 –39 GeV journal November 2012
Charged elliptic flow at zero charge asymmetry journal July 2013
Fluctuations of charge separation perpendicular to the event plane and local parity violation in s NN = 200 GeV Au + Au collisions at the BNL Relativistic Heavy Ion Collider journal December 2013
Measurement of charge multiplicity asymmetry correlations in high-energy nucleus-nucleus collisions at s N N = 200 GeV journal April 2014
Realistic implementation of chiral magnetic wave in heavy ion collisions journal April 2014
Chiral magnetic wave in an expanding QCD fluid journal February 2015
hijing: A Monte Carlo model for multiple jet production in pp , pA , and AA collisions journal December 1991
Quantum anomalies in dense matter journal October 2004
Anomalous axion interactions and topological currents in dense matter journal August 2005
Chiral magnetic effect journal October 2008
Normal ground state of dense relativistic matter in a magnetic field journal April 2011
Azimuthal Charged-Particle Correlations and Possible Local Strong Parity Violation journal December 2009
Testing the Chiral Magnetic and Chiral Vortical Effects in Heavy Ion Collisions journal February 2011
Chiral Magnetic Wave at Finite Baryon Density and the Electric Quadrupole Moment of the Quark-Gluon Plasma journal July 2011
Charge separation relative to the reaction plane in Pb-Pb collisions at s N N = 2.76     TeV journal January 2013
Observation of an Energy-Dependent Difference in Elliptic Flow between Particles and Antiparticles in Relativistic Heavy Ion Collisions journal April 2013
Beam-Energy Dependence of Charge Separation along the Magnetic Field in Au + Au Collisions at RHIC journal July 2014

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Electromagnetic fields and anomalous transports in heavy-ion collisions—a pedagogical review journal June 2016
Status of the chiral magnetic effect and collisions of isobars journal June 2017
Quantifying the chiral magnetic effect from anomalous-viscous fluid dynamics journal January 2018
Charge asymmetry dependence of flow and a novel correlator to detect the chiral magnetic wave in a multiphase transport model journal December 2019
Complications in the interpretation of the charge-asymmetry-dependent π flow for the chiral magnetic wave journal January 2020
Vorticity in heavy-ion collisions journal June 2016
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Effect of magnetic fields on pairs of oppositely charged particles in ultrarelativistic heavy-ion collisions journal April 2019
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Charge-Dependent Directed Flow in Cu+Au Collisions at sNN =200 GeV text January 2017
Chiral vortical wave and induced flavor charge transport in a rotating quark-gluon plasma text January 2015
Electromagnetic fields and anomalous transports in heavy-ion collisions --- A pedagogical review text January 2015
Off-equilibrium sphaleron transitions in the Glasma text January 2016
Vorticity in Heavy-Ion Collisions text January 2016
Quantifying Chiral Magnetic Effect from Anomalous-Viscous Fluid Dynamics text January 2016
Non-equilibrium study of the Chiral Magnetic Effect from real-time simulations with dynamical fermions text January 2016
Nuclear cluster structure effect on elliptic and triangular flows in heavy-ion collisions text January 2017


Figures / Tables (4)