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arXiv · 1705.01493

Extracting $\hat{q}$ in event-by-event hydrodynamics and the centrality/energy puzzle

Carlota Andres·Nestor Armesto·Harri Niemi·Risto Paatelainen·Carlos A. Salgado·Pia Zurita
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Abstract

In our analysis, we combine event-by-event hydrodynamics, within the EKRT formulation, with jet quenching -ASW Quenching Weights- to obtain high-$p_T$ $R_{\rm AA}$ for charged particles at RHIC and LHC energies for different centralities. By defining a $K$-factor that quantifies the departure of $\hat{q}$ from an ideal estimate, $K = \hat{q}/(2ε^{3/4})$, we fit the single-inclusive experimental data for charged particles. This $K$-factor is larger at RHIC than at the LHC but, surprisingly, it is almost independent of the centrality of the collision.

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Carlota Andres, Nestor Armesto, Harri Niemi, Risto Paatelainen, Carlos A. Salgado, Pia Zurita. 2017-05-03. Extracting $\hat{q}$ in event-by-event hydrodynamics and the centrality/energy puzzle. https://doi.org/10.1016/j.nuclphysa.2017.05.115

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