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Quark Coalescence for Charmed Mesons in Ultrarelativistic Heavy-Ion Collisions

V. Greco·C. M. Ko·R. Rapp
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Abstract

We investigate effects of charm-quark interactions in a Quark-Gluon Plasma on the production of $D$ and $J/ψ$ mesons in high-energy heavy-ion collisions. Employing a previously constructed coalescence model that successfully reproduces the transverse momentum ($p_T$) spectra and elliptic flow ($v_2(p_T)$) of light hadrons at RHIC from underlying light-quark distributions at the phase transition temperature $T_c$, $D$-meson and $J/ψ$ $p_T$ spectra are evaluated. For the charm-quark distributions, we consider two limiting scenarios: (i) {\em no} rescattering, corresponding to perturbative QCD spectra and (ii) {\em complete} thermalization including transverse expansion. With the $D$-meson spectra acquiring a minimal $v_2$ inherited from their light-quark content, the corresponding semileptonic decay spectra of single electrons are found to practically preserve the $v_2$ of the parent particles, exhibiting marked differences between the pQCD and thermal scenarios for $p_T\ge 1$ GeV. Likewise, the $p_T$-spectra and yields of $J/ψ$'s differ appreciably in the two scenarios.

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V. Greco, C. M. Ko, R. Rapp. 2004-10-05. Quark Coalescence for Charmed Mesons in Ultrarelativistic Heavy-Ion Collisions. https://doi.org/10.1016/j.physletb.2004.06.064

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