Measurement of charge multiplicity asymmetry correlations in high-energy nucleus-nucleus collisions at root S-NN=200 GeV

0428462 - ÚJF 2015 RIV US eng J - Journal Article
Adamczyk, L. - Adkins, J. K. - Agakishiev, G. - Aggarwal, M. M. - Ahammed, Z. - Alakhverdyants, A. V. - Alekseev, I. - Alford, J. - Anson, C. - Barnovská, Zuzana - Bielčík, J. - Bielčíková, Jana - Chaloupka, P. - Chung, Paul - Hajková, O. - Kapitán, Jan - Pachr, M. - Rusňák, Jan - Šumbera, Michal - Tlustý, David … Total 364 authors
Measurement of charge multiplicity asymmetry correlations in high-energy nucleus-nucleus collisions at root S-NN=200 GeV.
Physical Review. C. Roč. 89, č. 4 (2014), 044908. ISSN 0556-2813
R&D Projects: GA ČR GA13-20841S
Institutional support: RVO:61389005
Keywords : STAR collaboration * heavy ion collisions * charge multiplicity asymmetries
Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders
Impact factor: 3.733, year: 2014

A study is reported of the same-and opposite-sign charge-dependent azimuthal correlations with respect to the event plane in Au+ Au collisions at root(S)(NN) = 200 GeV. The charge multiplicity asymmetries between the up/down and left/right hemispheres relative to the event plane are utilized. The contributions from statistical fluctuations and detector effects were subtracted from the (co-) variance of the observed charge multiplicity asymmetries. In the mid-to most-central collisions, the same- (opposite-) sign pairs are preferentially emitted in back-to-back (aligned on the same-side) directions. The charge separation across the event plane, measured by the difference, Delta, between the like-and unlike-sign up/down-left/right correlations, is largest near the event plane. The difference is found to be proportional to the event-by-event final-state particle ellipticity (via the observed second order harmonic nu(obs)(2)), where Delta = [ 1.3 +/- 1.4( stat)(-1.0)(+4.0)(syst)] x 10(-5) + [3.2 +/- 0.2(stat)(- 0.3)(+0.4)(syst)] x 10(-3)v(2)(obs) for 20- 40% Au + Au collisions. The implications for the proposed chiral magnetic effect are discussed.
Permanent Link: http://hdl.handle.net/11104/0233807