784 research outputs found
A new method for the experimental study of topological effects in the quark-gluon plasma
A new method is presented for the quantitative measurement of charge
separation about the reaction plane. A correlation function is obtained whose
shape is concave when there is a net separation of positive and negative
charges. Correlations not specifically associated with charge, from flow, jets
and momentum conservation, do not influence the shape or magnitude of the
correlation function. Detailed simulations are used to demonstrate the
effectiveness of the method for the quantitative measurement of charge
separation. Such measurements are a pre-requisite to the investigation of
topological charge effects in the QGP as derived from the "strong
problem".Comment: Six pages 13 figures. Submitted for publicatio
Glauber-based evaluations of the odd moments of the initial eccentricity relative to the even order participant planes
Monte Carlo simulations are used to compute the centrality dependence of the
odd moments of the initial eccentricity , relative to the even
order (n) participant planes in Au+Au collisions. The results
obtained for two models of the eccentricity -- the Glauber and the factorized
Kharzeev-Levin-Nardi (fKLN) models -- indicate magnitudes which are essentially
zero. They suggest that a possible correlation between the orientations of the
the odd and even participant planes ( and
respectively), do not have a significant influence on the calculated
eccentricities. An experimental verification test for correlations between the
orientations of the the odd and even participant planes is also proposed.Comment: 3 pages, 1 figure. Version accepted for publicatio
A New Correlator to Detect and Characterize the Chiral Magnetic Effect
A charge-sensitive in-event correlator is proposed and tested for its
efficacy to detect and characterize charge separation associated with the
Chiral Magnetic Effect (CME) in heavy ion collisions. Tests, performed with the
aid of two reaction models, indicate discernible responses for background- and
CME-driven charge separation, relative to the second- () and
third-order () event planes, which could serve to identify the CME.
The tests also indicate a degree of sensitivity which would enable robust
characterization of the CME via Anomalous Viscous Fluid Dynamics (AVFD) model
comparisons.Comment: 5 pages, 5 Figs.; Published versio
Chiral magnetic wave at finite baryon density and the electric quadrupole moment of quark-gluon plasma in heavy ion collisions
Chiral Magnetic Wave (CMW) is a gapless collective excitation of quark-gluon
plasma in the presence of external magnetic field that stems from the interplay
of Chiral Magnetic (CME) and Chiral Separation Effects (CSE); it is composed by
the waves of the electric and chiral charge densities coupled by the axial
anomaly. We consider CMW at finite baryon density and find that it induces the
electric quadrupole moment of the quark-gluon plasma produced in heavy ion
collisions: the "poles" of the produced fireball (pointing outside of the
reaction plane) acquire additional positive electric charge, and the "equator"
acquires additional negative charge. We point out that this electric quadrupole
deformation lifts the degeneracy between the elliptic flows of positive and
negative pions leading to , and estimate the magnitude
of the effect.Comment: 4 pages, 3 figure
- …