Measurement of charge multiplicity asymmetry correlations in high energy nucleus-nucleus collisions at √sNN = 200 GeV

• Autor: L Adamczyk
• Lucas Mafia de Lima; Marcelo Gameiro Munhoz; Renato Aparecido Negrão de Oliveira; Ulisses Gulart de Souza; Alexandre Alarcon do Passo Suaide; Alejandro Szanto de Toledo
• Assuntos: COLISÕES DE ÍONS PESADOS RELATIVÍSTICOS
• Notas: arXiv.1303.0901
  
• Descrição: 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 √sNN = 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-)variance3 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, ∆, 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 v obs 2 ), where ∆ = (1.3±1.4(stat)+4.0 −1.0 (syst))×10−5 + (3.2±0.2(stat)+0.4 −0.3 (syst))×10−3 v obs 2 for 20-40% Au+Au collisions. The implications for the proposed chiral magnetic effect (CME) are discussed.
  
• Editor: São Paulo
  
• Data de criação/publicação: 2013
  
• Formato: 26 p.
  
• Idioma: Inglês