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Pseudorapidity dependence of parton energy loss in relativistic heavy ion collisions

Tetsufumi Hirano·Yasushi Nara
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Abstract

We analyze the recent data from the BRAHMS Collaboration on the pseudorapidity dependence of nuclear modification factors in Au+Au collisions at $\sqrt{s_{NN}}$ = 200 GeV by using the full three dimensional hydrodynamic simulations for the density effects on parton energy loss. We first compute the transverse spectra at $η=0$ and 2.2, and next take a ratio $R_η=R_{AA}(η=2.2)/R_{AA}(η=0)$, where $R_{AA}$ is a nuclear modification factor. It is shown that hydrodynamic components account for $R_η\simeq 1$ at low $p_\mathrm{T}$ and that quenched pQCD components lead $R_η < 1$ at high $p_\mathrm{T}$ which are consistent with the data. Strong suppression at $η=2.2$ is compatible with the parton energy loss in the final state.

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Tetsufumi Hirano, Yasushi Nara. 2003-10-23. Pseudorapidity dependence of parton energy loss in relativistic heavy ion collisions. https://doi.org/10.1103/physrevc.68.064902

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