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arXiv · 0802.2525

Towards an understanding of the RHIC single electron data

P. B. Gossiaux·J. Aichelin
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Abstract

High transverse momentum ($p_T$) single non-photonic electrons which have been measured in the RHIC experiments come dominantly from heavy meson decay. The ratio of their $p_T$ spectra in pp and AA collisions ($R_{AA}(p_T)$) reveals the energy loss of heavy quarks in the environment created by AA collisions. Using a fixed coupling constant and the Debye mass ($m_D\approx gT$) as infrared regulator perturbative QCD (pQCD) calculations are not able to reproduce the data, neither the energy loss nor the azimuthal $(v_2)$ distribution. Employing a running coupling constant and replacing the Debye mass by a more realistic hard thermal loop (HTL) calculation we find a substantial increase of the collisional energy loss which brings the $v_2(p_T)$ distribution as well as $R_{AA}(p_T)$ to values close to the experimental ones without excluding a contribution from radiative energy loss.

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P. B. Gossiaux, J. Aichelin. 2008-06-18. Towards an understanding of the RHIC single electron data. https://doi.org/10.1103/physrevc.78.014904

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