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arXiv · 1202.1047

Jet Tomography of Harmonic Fluctuations in the Initial Condition of Heavy Ion Collisions

Xilin Zhang·Jinfeng Liao
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Abstract

In this paper we study the jet response (particularly azimuthal anisotropy) as a hard probe of the harmonic fluctuations in the initial condition of central heavy ion collisions. By implementing the fluctuations via cumulant expansion for various harmonics quantified by $ε_n$ and using the geometric model for jet energy loss, we compute the response $χ^h_n=v_n/ε_n$. Combining these results with the known hydrodynamic response of the bulk matter expansion in the literature, we show that the hard-soft azimuthal correlation arising from their respective responses to the common geometric fluctuations reveals a robust and narrow near-side peak that may provide the dominant contribution to the "hard-ridge" observed in experimental data.

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Xilin Zhang, Jinfeng Liao. 2012-06-08. Jet Tomography of Harmonic Fluctuations in the Initial Condition of Heavy Ion Collisions. https://doi.org/10.1016/j.physletb.2012.05.040

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