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arXiv · 2110.00622

Strangeness neutral equation of state with a critical point

Abstract

We formulate a family of equations of state for Quantum Chromodynamics that exhibit critical features and obey the charge conservation conditions present in heavy-ion collisions (HICs). This construction utilizes the first-principle Lattice QCD (LQCD) results up to $\mathcal{O}(μ_B^4)$ by matching the Taylor coefficients at each order. The criticality of the equation of state (EoS) is implemented based on the well-established principle of universal scaling behavior, where QCD belongs to the 3D Ising Model universality class. The critical point can be placed in a range of temperature and baryonic chemical potential relevant for the Beam Energy Scan II at RHIC. Furthermore, the strength of the critical features can be varied as well. This flexibility is embedded in four free parameters, that could potentially be constrained by the experimental data. We will discuss the features and versatility of our EoS, as well as present the relevant thermodynamic quantities which are important for hydrodynamical simulations of HICs.

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Jamie M. Karthein, Debora Mroczek, Angel R. Nava Acuna, Jacquelyn Noronha-Hostler, Paolo Parotto, Damien R. P. Price, Claudia Ratti. 2021-10-01. Strangeness neutral equation of state with a critical point. https://arxiv.org/abs/2110.00622

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