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  • Letter
  • Open Access

Real-time evolution of critical modes in the QCD phase diagram

Yang-yang Tan1, Shi Yin2, Yong-rui Chen2, Chuang Huang3, and Wei-jie Fu1,*

  • *Contact author: wjfu@dlut.edu.cn
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Phys. Rev. D 114, L011501 – Published 6 July, 2026

DOI: https://doi.org/10.1103/hy7v-z3vz

Abstract

We develop a QCD-assisted relaxation dynamic model for the critical mode of the critical end point (CEP) in the QCD phase diagram, which allows us to investigate the critical slowing-down effect quantitatively in the QCD phase diagram, especially in the proximity of the CEP, without any phenomenological parameters. The relaxation time from nonequilibrium to equilibrium in the QCD phase diagram is extracted from the Langevin simulations of the QCD-assisted relaxation dynamic model. It is found that in a narrow region along the phase boundary radiated from the CEP, the relaxation time is enhanced significantly. Outside this narrow region, the relaxation time drops drastically, which implies that the dynamic critical region is small in the QCD phase diagram. Within the present setup in this work, we further find that the relaxation time is not strongly enhanced along the considered chemical freeze-out curves, suggesting that the effects of critical slowing down may be limited there.

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Phys. Rev. D 114, L011501– Published 6 July, 2026
  • Received 13 January 2026
  • Accepted 12 June 2026
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