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arXiv · 0908.3344

Dileptons, Charm and Charmonium at Finite Temperature and Chemical Potential

Ralf Rapp
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Abstract

We discuss how dileptons, open charm and charmonia may be utilized in heavy-ion collisions to extract information specific to hot and dense matter at finite quark chemical potential, $μ_q$. For each observable we briefly discuss underlying theoretical frameworks and the current status in interpreting available heavy-ion data at SPS and RHIC energies. Low-mass dileptons are particularly sensitive to baryonic medium effects in spectral modifications of the $ρ$ meson, and may serve as an accurate measure of the fireball lifetime. In the open-charm sector, observable signals may be generated by a ``critical'' enhancement of scattering rates via $t$-channel exchange of a soft $σ$ mode. For charmonia, finite-$T$ potential models could be used to extrapolate color-screening effects to finite $μ_q$ to facilitate a quantitative evaluation of dissociation rates in the medium.

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Ralf Rapp. 2009-08-23. Dileptons, Charm and Charmonium at Finite Temperature and Chemical Potential. https://arxiv.org/abs/0908.3344

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