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arXiv · 1805.04445

Higher order fluctuations and correlations of conserved charges from lattice QCD

Szabolcs Borsanyi·Zoltan Fodor·Jana N. Guenther·Sandor K Katz·Kalman K. Szabo·Attila Pasztor·Israel Portillo·Claudia Ratti
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Abstract

We calculate several diagonal and non-diagonal fluctuations of conserved charges in a system of 2+1+1 quark flavors with physical masses, on a lattice with size $48^3\times12$. Higher order fluctuations at $μ_B=0$ are obtained as derivatives of the lower order ones, simulated at imaginary chemical potential. From these correlations and fluctuations we construct ratios of net-baryon number cumulants as functions of temperature and chemical potential, which satisfy the experimental conditions of strangeness neutrality and proton/baryon ratio. Our results qualitatively explain the behavior of the measured cumulant ratios by the STAR collaboration.

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Szabolcs Borsanyi, Zoltan Fodor, Jana N. Guenther, Sandor K Katz, Kalman K. Szabo, Attila Pasztor, Israel Portillo, Claudia Ratti. 2018-05-11. Higher order fluctuations and correlations of conserved charges from lattice QCD. https://doi.org/10.1007/jhep10(2018)205

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