Effects of equation of state on nuclear suppression and the initial entropy density of quark gluon plasma

TL;DR

This paper investigates how the equation of state influences nuclear suppression of heavy flavors in quark-gluon plasma and estimates the initial entropy density at RHIC energies using experimental data and lattice QCD inputs.

Contribution

It provides a novel analysis linking the equation of state to initial entropy density estimates in quark-gluon plasma, incorporating lattice QCD data to reduce model dependence.

Findings

Initial entropy density ranges from 20 to 59 /fm$^3$ depending on the sound velocity.

Conservative estimate of initial entropy density is about 20 /fm$^3$.

Initial temperature is approximately 210 MeV, above the lattice QCD transition temperature.

Abstract

We study the effects of the equation of state on the nuclear suppression of heavy flavours in quark gluon plasma and estimate the initial entropy density of the system produced at the highest RHIC energy. For this purpose we have used the experimental data on the charged particle multiplicity and the nuclear suppression of single electron spectra originating from the semi-leptonic decays of open charm and beauty mesons. We have used inputs from lattice QCD to minimize the model dependence of the results. We obtain the value of the initial entropy density which varies from 20 to 59 /fm$^3$ depending on the value of the velocity of sound that one uses for the analysis. Our investigation leads to a conservative value of the initial entropy density $\sim 20/$fm$^3$ with corresponding initial temperature $\sim 210$ MeV well above the value of the transition temperature predicted by lattice QCD.