Principal component analysis of the nonlinear coupling of harmonic modes in heavy-ion collisions

Understand

The principal component analysis of flow correlations in heavy-ion collisions is studied.

• The correlation matrix of harmonic flow is generalized to correlations involving several different flow vectors.
• The method can be applied to study the nonlinear coupling between different harmonic modes in a double differential way in transverse momentum or pseudorapidity.
• The procedure is illustrated with results from the hydrodynamic model applied to Pb+Pb collisions at $\sqrt{s}=2760$GeV.