Principal Component Analysis of collective flow in Relativistic Heavy-Ion Collisions

Ziming Liu; Wenbin Zhao; Huichao Song

doi:10.1140/epjc/s10052-019-7379-y

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arXiv · 1903.09833

Principal Component Analysis of collective flow in Relativistic Heavy-Ion Collisions

Ziming Liu·Wenbin Zhao·Huichao Song

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Abstract

In this paper, we implement Principal Component Analysis (PCA) to study the single particle distributions generated from thousands of {\tt VISH2+1} hydrodynamic simulations with an aim to explore if a machine could directly discover flow from the huge amount of data without explicit instructions from human-beings. We found that the obtained PCA eigenvectors are similar to but not identical with the traditional Fourier bases. Correspondingly, the PCA defined flow harmonics $v_n^\prime$ are also similar to the traditional $v_n$ for $n=2$ and 3, but largely deviated from the Fourier ones for $n\geq 4$. A further study on the symmetric cumulants and the Pearson coefficients indicates that mode-coupling effects are reduced for these flow harmonics defined by PCA.

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Ziming Liu, Wenbin Zhao, Huichao Song. 2019-03-23. Principal Component Analysis of collective flow in Relativistic Heavy-Ion Collisions. https://doi.org/10.1140/epjc%2Fs10052-019-7379-y

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