Finite-Size Scaling of Thermal Susceptibility and Specific Heat Density Near the QCD Deconfinement Phase Transition

  • B. Moussaoui Particle and Statistical Physics Laboratory, Ecole Normale Sup´erieure-Kouba, Vieux-Kouba, Algiers, Algeria; Theoretical Physics Laboratory, Faculty of Physics, USTHB Bab-Ezzouar, El Alia, Algiers, Algeria https://orcid.org/0000-0001-8580-9412
  • A. Ait El Djoudi Laboratoire de Physique des Particules et Physique Statsitique, Ecole Normale Supérieure-Kouba, Vieux-Kouba, Algiers https://orcid.org/0009-0005-7773-0401
  • H. Mouloudj Particle and Statistical Physics Laboratory, Ecole Normale Sup´erieure-Kouba, Vieux-Kouba, Algiers, Algeria; Hassiba Benbouali University, Chlef, Algeria https://orcid.org/0009-0006-0376-9642
  • M.A. Lakehal Particle and Statistical Physics Laboratory, Ecole Normale Sup´erieure-Kouba, Vieux-Kouba, Algiers, Algeria; M’hamed Bougara University, Boumerdes, Algeria https://orcid.org/0009-0007-8930-0454
DOI: https://doi.org/10.26565/2312-4334-2026-3-12
Keywords: Thermally driven deconfinement phase transition (DPT), Color-singlet, Quark chemical potential, Finite-size scaling (FSS) analysis, Transition temperature

Abstract

The properties of the thermally driven deconfinement phase transition (DPT) from a hadronic gas (HG) to a color-singlet quark-gluon plasma (QGP) containing gluons and massless up and down quarks, at a nonzero quark chemical potential μ, are investigated by considering the volumetric coexistence of the hadronic gas and the QGP in a finite-size system. Finite-size effects are analyzed for the thermally driven DPT at different μ values. The critical exponents are determined using a numerical finite-size scaling (FSS) analysis, by fitting the results as a function of the system size. The effective transition temperature (Tc) exhibits a shift toward higher values as the system size decreases, indicating a critical behavior in the region of the thermally driven DPT from a HG to the QGP. Crucially, all three scaling critical exponents are found to be independent of the quark chemical potential μ, establishing the universality of the finite-size scaling structure with respect to μ.

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Published
2026-09-07
Cited
How to Cite
Moussaoui, B., El Djoudi, A. A., Mouloudj, H., & Lakehal, M. (2026). Finite-Size Scaling of Thermal Susceptibility and Specific Heat Density Near the QCD Deconfinement Phase Transition. East European Journal of Physics, (3), 138-145. https://doi.org/10.26565/2312-4334-2026-3-12
Issue
No. 3 (2026): East European Journal of Physics
Section
Original Papers

Copyright (c) 2026 B. Moussaoui, Amal Ait El Djoudi, H. Mouloudj, M.A. Lakehal

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