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  • Open Access

Scaling properties of net-baryon number fluctuations at the deconfinement critical point

Michał Szymański* and Pok Man Lo

Krzysztof Redlich

Chihiro Sasaki

  • Institute of Theoretical Physics, University of Wrocław, Plac Maksa Borna 9, PL-50204 Wrocław, Poland and International Institute for Sustainability with Knotted Chiral Meta Matter (WPI-SKCM2), Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8531, Japan

  • *Contact author: michal.szymanski@uwr.edu.pl
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Phys. Rev. D 114, 074007 – Published 2 October, 2026

DOI: https://doi.org/10.1103/lcgf-r6vy

Abstract

We investigate the critical behavior of the first four cumulants of the net-baryon number near the deconfinement critical point in QCD in the limit of heavy quarks. By connecting baryon-number fluctuations to Polyakov loop susceptibilities, we analyze their mean-field scaling properties at zero and nonzero baryon chemical potentials. In the mean-field approximation we derive critical exponents via the Landau theory and validate them through explicit numerical calculations in an effective Polyakov loop model. Using a Ginzburg-Landau criterion as a diagnostic of beyond-mean-field effects, we estimate the size of the critical region and find that it shrinks with increasing baryon density. By utilizing the exact scaling function in the 3D Ising model, we estimate critical exponents beyond the mean-field approximation.

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Phys. Rev. D 114, 074007– Published 2 October, 2026
  • Received 21 May 2026
  • Accepted 28 August 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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