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arXiv · 0804.3655

Reexamination for the calculation of elliptic flow and other fourier harmonics

Xiao-Mei Li·Bao-Guo Dong·Yu-Liang Yan·Hai-Liang Ma·Dai-Mei Zhou·Ben-Hao Sa
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Abstract

We have argued that the azimuthal symmetry and asymmetry components in fourier expansion of particle momentum azimuthal distribution, $v_n$ (n=0, 1, 2, ...), should be calculated as an average of $cos(nϕ)$ first over particles in an event and then over events (event-wise average) rather than "an average over all particles in all events" (particle-wise average). In case of large centrality (multiplicity) bin the particle-wise average is not accurate because the influence (fluctuation) of particle multiplicity was not taken into account.

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Xiao-Mei Li, Bao-Guo Dong, Yu-Liang Yan, Hai-Liang Ma, Dai-Mei Zhou, Ben-Hao Sa. 2009-12-16. Reexamination for the calculation of elliptic flow and other fourier harmonics. https://arxiv.org/abs/0804.3655

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