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arXiv · 1407.7436

Azimuthal Jet Tomography at RHIC and LHC

Barbara Betz·Miklos Gyulassy
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Abstract

Results based on a generic jet-energy loss model that interpolates between running coupling pQCD-based and AdS/CFT-inspired holographic prescriptions are compared to recent data on the high-p_T pion nuclear modification factor and the high-p_T elliptic flow in nuclear collisions at RHIC and LHC. The jet-energy loss model is coupled to various (2+1)d (viscous hydrodynamic) fields. The impact of energy-loss fluctuations is discussed. While a previously proposed AdS/CFT jet-energy loss model with a temperature-independent jet-medium coupling is shown to be inconsistent with the LHC data, we find a rather broad class of jet-energy independent energy-loss models $dE/dx= κ(T) x^z T^{2+z}$ that can account for the current data with different temperature-dependent jet-medium couplings $κ(T)$ and path-length dependence exponents of $0\le z \le 2$.

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Barbara Betz, Miklos Gyulassy. 2014-07-28. Azimuthal Jet Tomography at RHIC and LHC. https://doi.org/10.1016/j.nuclphysa.2014.08.109

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