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arXiv · 2003.01147

Momentum-dependent flow fluctuations as a hydrodynamic response to initial geometry

Maurício Hippert·David Dobrigkeit Chinellato·Matthew Luzum·Jorge Noronha·Tiago Nunes da Silva·Jun Takahashi
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Abstract

We propose a redefinition of the principal component analysis (PCA) of anisotropic flow that makes it more directly connected to fluctuations of the initial geometry of the system. Then, using state-of-the-art hydrodynamic simulations, we make an explicit connection between flow fluctuations and a cumulant expansion of the initial transverse geometry. In particular, we show that the second principal component of elliptic flow is generated by higher-order cumulants, and therefore probes smaller length scales of the initial state. With this information, it will be possible to put new constraints on properties of the early-time dynamics of a heavy-ion collision, including small-scale structure, as well as properties of the quark-gluon plasma.

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Maurício Hippert, David Dobrigkeit Chinellato, Matthew Luzum, Jorge Noronha, Tiago Nunes da Silva, Jun Takahashi. 2020-03-02. Momentum-dependent flow fluctuations as a hydrodynamic response to initial geometry. https://doi.org/10.1016/j.nuclphysa.2020.121982

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