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arXiv · 1007.2580

The QCD equation of state with dynamical quarks

Szabolcs Borsanyi·Gergely Endrodi·Zoltan Fodor·Antal Jakovac·Sandor D. Katz·Stefan Krieg·Claudia Ratti·Kalman K. Szabo
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Abstract

The present paper concludes our investigation on the QCD equation of state with 2+1 staggered flavors and one-link stout improvement. We extend our previous study [JHEP 0601:089 (2006)] by choosing even finer lattices. Lattices with $N_t=6,8$ and 10 are used, and the continuum limit is approached by checking the results at $N_t=12$. A Symanzik improved gauge and a stout-link improved staggered fermion action is utilized. We use physical quark masses, that is, for the lightest staggered pions and kaons we fix the $m_\pi/f_K$ and $m_K/f_K$ ratios to their experimental values. The pressure, the interaction measure, the energy and entropy density and the speed of sound are presented as functions of the temperature in the range $100 ...1000 \textmd{MeV}$. We give estimates for the pion mass dependence and for the contribution of the charm quark. We compare our data to the equation of state obtained by the "hotQCD" collaboration.

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Szabolcs Borsanyi, Gergely Endrodi, Zoltan Fodor, Antal Jakovac, Sandor D. Katz, Stefan Krieg, Claudia Ratti, Kalman K. Szabo. 2010-07-15. The QCD equation of state with dynamical quarks. https://doi.org/10.1007/jhep11(2010)077

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