Non-flow correlations and elliptic flow fluctuations in Au + Au collisions at √sNN = 200 GeV

This article presents results on event-by-event elliptic flow fluctuations in Au + Au collisions at √s NN = 200 GeV, where the contribution from non-flow correlations has been subtracted. An analysis method is introduced to measure non-flow correlations, relying on the assumption that non-flow correlations are most prominent at short ranges (|Δη| 2), relative elliptic flow fluctuations of approximately 30-40% are observed. These results are consistent with predictions based on spatial fluctuations of the participating nucleons in the initial nuclear overlap region. It is found that the long-range non-flow correlations in Au + Au collisions would have to be more than an order of magnitude stronger compared to the p + p data to lead to the observed azimuthal anisotropy fluctuations with no intrinsic elliptic flow fluctuations.