We present first, preliminary results for the QCD equation of state with 2+1+1 flavors of highly improved staggered quarks (HISQ), that is, including the effects of a dynamical charm quark. This first study uses a line of constant physics (LCP) with the light-quark mass at ml = ms/5 and physical strange- and charm-quark masses. With increasing temperature, the effects of the charm quark, as in earlier partially quenched studies, start to be visible at temperatures where the equation of state is becoming insensitive to the value of the light (up/down) quark mass.
|Original language||English (US)|
|Journal||Proceedings of Science|
|Publication status||Published - 2012|
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