Plasma screening and the critical end point in the QCD phase diagram


  • Alejandro Ayala ICN-UNAM
  • B. Almeida Universidad de Sonora
  • J. J. Cobos-Martínez Universidad de Sonora
  • S. Hernández-Ortiz University of Washington
  • L. Hernández Universidad Autónoma Metropolitana
  • A. Raya Universidad Michoacana de San Nicolás de Hidalgo
  • M. E. Tejeda-Yeomans Universidad de Colima



Linear Sigma Model, CEP, HRGM


In heavy-ion collisions, fluctuations of conserved charges are known to be sensitive observables to probe criticality for the QCD phase transition and to locate the position of the putative critical end point (CEP). In this work we seek to show that the Linear Sigma Model with quarks produces an effective description of the QCD phase diagram in which deviations from a Hadron Resonance Gas are due to plasma screening effects, encoded in the contribution of the ring diagrams. Accounting for these, it is possible to include in the description the effect of long-range correlations. To set the model parameters we use LQCD results for the crossover transition at vanishing chemical potential. Finally, studying baryon number fluctuations from the model, we show that the CEP can be located within the HADES and/or the lowest end of the NICA energy domain, √ sNN ∼ 2 GeV.


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How to Cite

Ayala A, Almeida B, Cobos-Martínez JJ, Hernández-Ortiz S, Hernández L, Raya A, Tejeda-Yeomans ME. Plasma screening and the critical end point in the QCD phase diagram. Supl. Rev. Mex. Fis. [Internet]. 2022 Dec. 10 [cited 2023 Feb. 6];3(4):040917 1-8. Available from: