2009/07/31 by E. Nakano, B. -J. Schaefer, Bernd-Jochen Schaefer +5
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-lat #hep-ph #hep-th #nucl-th
paper · pdf · doi:10.1016/j.physletb.2009.11.027
published as Phys.Lett.B682:401-407,2010 · 9 pages, 4 figures, refs added, version to be published in Phys. Lett. B
openalex publication_date 2009/11/16 · arxiv created 2009/11/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/02
Isentropic trajectories crossing the chiral phase transition near the critical endpoint (CEP) are studied for two light quark flavors. The calculations are performed within an effective chiral model with quark–meson interactions, belonging to the same universality class as QCD. We confront mean-field thermodynamics with the functional renormalization group approach, where fluctuations are properly taken into account. We establish a connection between modifications of the isentropic trajectories found in mean-field calculations at the crossover transition near the CEP and the order of the phase transition in the chiral limit. Furthermore, the isentropes obtained with the renormalization group are completely smooth at the crossover transition and do not in any way reflect the proximity of the CEP. In particular, our results do not show the recently conjectured focusing of isentropes from the crossover region towards the critical endpoint.