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  • Letter
  • Open Access

Lattice QCD constraints on the critical point from an improved precision equation of state

Szabolcs Borsányi1, Zoltán Fodor2,3,1,4,5, Jana N. Guenther1, Paolo Parotto6, Attila Pásztor4, Claudia Ratti7, Volodymyr Vovchenko7, and Chik Him Wong1

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Phys. Rev. D 112, L111505 – Published 17 December, 2025

DOI: https://doi.org/10.1103/rj6r-dmg9

Abstract

In this paper we employ lattice simulations to search for the critical point of QCD. We search for the onset of a first-order QCD transition on the phase diagram by following contours of constant entropy density from imaginary to real chemical potentials under conditions of strangeness neutrality. We scan the phase diagram and investigate whether these contours meet to determine the probability that the critical point is located in a certain region on the T−μB plane. To achieve this we introduce a new, continuum extrapolated equation of state at zero density with improved precision using lattices with Nτ=8, 10, 12, 16 time slices, and supplement it with new data at imaginary chemical potential. The current precision allows us to exclude, at the 2σ level, the existence of a critical point at μB<450  MeV.

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Phys. Rev. D 112, L111505– Published 17 December, 2025
  • Received 10 March 2025
  • Accepted 4 November 2025
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