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arXiv · 1906.08915

Measuring Momentum-Dependent Flow Fluctuations in Heavy-Ion Collisions

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

In heavy-ion collisions, momentum-dependent pair correlations can be characterized by a principal component analysis (PCA), in which subleading modes are expected to reveal new information on flow fluctuations. However, we find that, as currently measured, these modes can be dominated by multiplicity fluctuations, which serve as an unwanted background. Here, we propose new PCA observables that are robust against multiplicity fluctuations and isolate novel sources of flow fluctuations, thus being suited to provide fresh insight into the initial stages of the system at small length scales.

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Mauricio Hippert, David Dobrigkeit Chinellato, Matthew Luzum, Jorge Noronha, Tiago Nunes da Silva, Jun Takahashi. 2020-03-05. Measuring Momentum-Dependent Flow Fluctuations in Heavy-Ion Collisions. https://doi.org/10.1103/physrevc.101.034903

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