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arXiv · 2202.05574

Resummed lattice QCD equation of state at finite baryon density: strangeness neutrality and beyond

Szabolcs Borsanyi·Zoltan Fodor·Jana N. Guenther·Ruben Kara·Paolo Parotto·Attila Pasztor·Claudia Ratti·Kalman K. Szabo
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Abstract

We calculate a resummed equation of state with lattice QCD simulations at imaginary chemical potentials. This work presents a generalization of the scheme introduced in 2102.06660 to the case of non-zero $\mu_S$, focusing on the line of strangeness neutrality. We present results up to $\mu_B/T \leq 3.5$ on the strangeness neutral line $\left\langle S \right\rangle = 0$ in the temperature range $130 \rm{MeV} \leq T \leq 280 \rm{MeV}$. We also extrapolate the finite baryon density equation of state to small non-zero values of the strangeness-to-baryon ratio $R=\left\langle S \right\rangle / \left\langle B \right\rangle$. We perform a continuum extrapolation using lattice simulations of the 4stout-improved staggered action with 8, 10, 12 and 16 timeslices.

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Szabolcs Borsanyi, Zoltan Fodor, Jana N. Guenther, Ruben Kara, Paolo Parotto, Attila Pasztor, Claudia Ratti, Kalman K. Szabo. 2022-02-11. Resummed lattice QCD equation of state at finite baryon density: strangeness neutrality and beyond. https://doi.org/10.1103/physrevd.105.114504

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