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arXiv · 1612.06781

Extracting $\hat{q}$ from single inclusive data at RHIC and at the LHC for different centralities: a new puzzle?

Carlota Andres·Nestor Amesto·Matthew Luzum·Carlos A. Salgado·Pia Zurita
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Abstract

We present here an extraction of the jet transport coefficient, $\hat{q}$, using RHIC and LHC single-inclusive high-$p_T$ data for different centralities. We fit a $K$-factor that determines the deviation of this coefficient from an ideal estimate, $K \equiv \hat{q}/(2ε^{3/4})$, where $ε$ is given by hydrodynamic simulations. As obtained already in previous studies, this $K$-factor is found to be larger at RHIC than at the LHC. However it is, unexpectedly, basically no-dependent on the centrality of the collision. Taken at face value this result, the $K$-factor would not depend on local properties of the QGP as temperature, but on global collision variables such as the center of mass energy.

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Carlota Andres, Nestor Amesto, Matthew Luzum, Carlos A. Salgado, Pia Zurita. 2016-12-20. Extracting $\hat{q}$ from single inclusive data at RHIC and at the LHC for different centralities: a new puzzle?. https://arxiv.org/abs/1612.06781

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