A new 4D lattice QCD equation of state: extended density coverage from a generalized $T^\prime$-expansion

Ahmed Abuali; Szabolcs Borsányi; Zoltán Fodor; Johannes Jahan; Micheal Kahangirwe; Paolo Parotto; Attila Pásztor; Claudia Ratti; Hitansh Shah; Seth A. Trabulsi

arXiv · 2504.01881

A new 4D lattice QCD equation of state: extended density coverage from a generalized $T^\prime$-expansion

Ahmed Abuali·Szabolcs Borsányi·Zoltán Fodor·Johannes Jahan·Micheal Kahangirwe·Paolo Parotto·Attila Pásztor·Claudia Ratti·Hitansh Shah·Seth A. Trabulsi

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Abstract

We present a new equation of state for QCD in which the temperature $T$ and the three chemical potentials for baryon number $μ_B$, electric charge $μ_Q$ and strangeness $μ_S$ can be varied independently. This result is based on a generalization of the $T'$-expansion scheme, thanks to which the diagonal $μ_B$ extrapolation was pushed up to a baryo-chemical potential $μ_B/T \sim 3.5$ for the first time. This considerably extended the coverage of the Taylor expansion, limited to $μ_B/T < 2.5-3$. As a consequence, we are able to offer a substantially larger coverage of the four-dimensional QCD phase diagram as well, compared to previously available Taylor expansion results. Our results are based on new continuum estimated lattice results on the full set of second and fourth order fluctuations.

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Ahmed Abuali, Szabolcs Borsányi, Zoltán Fodor, Johannes Jahan, Micheal Kahangirwe, Paolo Parotto, Attila Pásztor, Claudia Ratti, Hitansh Shah, Seth A. Trabulsi. 2025-04-02. A new 4D lattice QCD equation of state: extended density coverage from a generalized $T^\prime$-expansion. https://arxiv.org/abs/2504.01881

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