# Higher order fluctuations and correlations of conserved charges from lattice QCD

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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} × 12. 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.

## Keywords

Lattice QCD Phase Diagram of QCD Quark-Gluon Plasma## Notes

### **Open Access**

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