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arXiv · 0903.4166

Nuclear modification factor of non-photonic electrons in heavy-ion collisions and the heavy-flavor baryon-to-meson ratio

Yongseok Oh·Che Ming Ko
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Abstract

The nuclear modification factor $R_{AA}$ of non-photonic electrons in ${Au} + {Au}$ collisions at $\sqrt{s_{NN}^{}} = 200$ GeV is studied by considering the decays of heavy-flavor hadrons produced in a quark coalescence model. Although an enhanced $Λ_c/D^0$ ratio is predicted by the coalescence model, it is peaked at small transverse momenta ($\sim 2$ GeV) due to the large difference between heavy and light quark masses. As a result, the enhanced $Λ_c/D^0$ ratio, which is expected to suppress the electron $R_{AA}$ as the branching ratio of $Λ_c$ decay into electrons is smaller than that of $D^0$, does not lead to additional suppression of the electron $R_{AA}$ at large transverse momenta ($\ge 5$ GeV), where the suppression is mainly due to heavy quark energy loss in produced quark-gluon plasma. Also, the enhanced $Λ_b/\bar{B}^0$ ratio predicted by the coalescence model has even smaller effect on the non-photonic electron $R_{AA}$ as bottom baryons and mesons have similar branching ratios for semi-leptonic decays into electrons.

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Yongseok Oh, Che Ming Ko. 2009-06-16. Nuclear modification factor of non-photonic electrons in heavy-ion collisions and the heavy-flavor baryon-to-meson ratio. https://doi.org/10.1103/physrevc.79.067902

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