Measurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central d+Au collisions at sNN =200 GeV
Article
Adare, A, Aidala, C, Ajitanand, NN et al. (2015). Measurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central d+Au collisions at sNN =200 GeV
. PHYSICAL REVIEW LETTERS, 114(19), 10.1103/PhysRevLett.114.192301
Adare, A, Aidala, C, Ajitanand, NN et al. (2015). Measurement of long-range angular correlation and quadrupole anisotropy of pions and (anti)protons in central d+Au collisions at sNN =200 GeV
. PHYSICAL REVIEW LETTERS, 114(19), 10.1103/PhysRevLett.114.192301
We present azimuthal angular correlations between charged hadrons and energy deposited in calorimeter towers in central d+Au and minimum bias p+p collisions at sNN=200GeV. The charged hadron is measured at midrapidity |η|<0.35, and the energy is measured at large rapidity (-3.7<η<-3.1, Au-going direction). An enhanced near-side angular correlation across |Δη|>2.75 is observed in d+Au collisions. Using the event plane method applied to the Au-going energy distribution, we extract the anisotropy strength v2 for inclusive charged hadrons at midrapidity up to pT=4.5GeV/c. We also present the measurement of v2 for identified π± and (anti)protons in central d+Au collisions, and observe a mass-ordering pattern similar to that seen in heavy-ion collisions. These results are compared with viscous hydrodynamic calculations and measurements from p+Pb at sNN=5.02TeV. The magnitude of the mass ordering in d+Au is found to be smaller than that in p+Pb collisions, which may indicate smaller radial flow in lower energy d+Au collisions.
