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arXiv · 1608.06610

Challenges in flow background removal in search for the chiral magnetic effect

Fuqiang Wang·Jie Zhao
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Abstract

We investigate the effect of resonance decays on the three-particle correlator charge separation observable in search for the chiral magnetic effect, using a simple simulation with realistic inputs. We find that resonance decays can largely account for the measured signal. We suppress the elliptic flow ($v_2$) background by using zero event-by-event $v_2$ (or via the mixed-event technique). We find that the background is suppressed, but not eliminated as naively anticipated. We identify the reason to be the non-identicalness of the resonance and final-state particle's $v_2$ and the induced correlation between the transverse momentum dependent resonance $v_2$ and decay angle. We make predictions for the charge separation signal due to resonance decays in 200~GeV Au+Au collisions.

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Fuqiang Wang, Jie Zhao. 2017-05-12. Challenges in flow background removal in search for the chiral magnetic effect. https://doi.org/10.1103/physrevc.95.051901

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