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DOE OSTI · 21499360

Event-plane flow analysis without nonflow effects

Bilandzic, Ante·Kolk, Naomi van der·Ollitrault, Jean-Yves·Snellings, Raimond
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Abstract

The event-plane method, which is widely used to analyze anisotropic flow in nucleus-nucleus collisions, is known to be biased by nonflow effects, especially at high p{sub t}. Various methods (cumulants, Lee-Yang zeros) have been proposed to eliminate nonflow effects, but their implementation is tedious, which has limited their application so far. In this article, we show that the Lee-Yang-zeroes method can be recast in a form similar to the standard event-plane analysis. Nonflow correlations are strongly suppressed by using the information from the length of the flow vector, in addition to the event-plane angle. This opens the way to improved analyses of elliptic flow and azimuthally sensitive observables at the Relativistic Heavy Ion Collider and the Large Hadron Collider.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSACCELERATORSANISOTROPYBARYON-BARYON INTERACTIONSBROOKHAVEN RHICCERN LHCCOLLISIONSCORRELATIONSCYCLIC ACCELERATORSHADRON-HADRON INTERACTIONSHEAVY ION ACCELERATORSINTERACTIONSNUCLEINUCLEON-NUCLEON INTERACTIONSPARTICLE INTERACTIONSSTORAGE RINGSSYNCHROTRONS

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Bilandzic, Ante, Kolk, Naomi van der, Ollitrault, Jean-Yves, Snellings, Raimond. 2011-01-15. Event-plane flow analysis without nonflow effects. https://doi.org/10.1103/physrevc.83.014909

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