2002/07/31 by Alejandro Ayala, A. Ayala, Paolo Amore +3 · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph #nucl-th
paper · pdf · doi:10.1103/physrevc.66.045205
published as Phys.Rev. C66 (2002) 045205 · 7 pages, 5 figures, 3 new references, published version
arxiv created 2002/10/24 · openalex publication_date 2002/10/28 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the behavior of the pion dispersion relation in a pion medium at finite density and temperature. We introduce a pion chemical potential to describe the finite pion number density and argue that such description is valid during the hadronic phase of a relativistic heavy-ion collision between chemical and thermal freeze-out. We make use of an effective Lagrangian that explicitly respects chiral symmetry through the enforcement of the chiral Ward identities. The pion dispersion relation is computed through the computation of the pion self-energy in a nonperturbative fashion by giving an approximate solution to the Schwinger-Dyson equation for this self-energy. The dispersion relation is described in terms of a density and temperature dependent mass and an index of refraction which is also temperature, density, as well as momentum dependent. The index of refraction is larger than unity for all values of the momentum for finite \ensuremathμ and T. We conclude by exploring some of the possible consequences for the propagation of pions through the boundary between the medium and vacuum.