QCD Phase Structure and In-Medium Modifications of Meson Masses in Polyakov Linear-Sigma Model with Finite Isospin Asymmetry

Abstract

In the QCD-like effective model, the Polyakov linear-sigma model, the isospin sigma field (σ¯3=fK±−fK0) and the third generator of the matrix of the explicit symmetry breaking [h3=ma02fK±−fK0] are estimated in terms of the decay constants of the neutral (fK0) and charged Kaon (fK±) and the mass of a0 meson. Both quantities σ¯3 and h3 are then evaluated, at finite baryon (μB), isospin chemical potential (μI), and temperature (T). Thereby, the dependence of the critical temperature on isospin chemical potential could be mapped out in the (T−μI) phase diagram In the QCD-like effective model, the Polyakov linear-sigma model, the isospin sigma field (σ¯3=fK±−fK0) and the third generator of the matrix of the explicit symmetry breaking [h3=ma02fK±−fK0] are estimated in terms of the decay constants of the neutral (fK0) and charged Kaon (fK±) and the mass of a0 meson. Both quantities σ¯3 and h3 are then evaluated, at finite baryon (μB), isospin chemical potential (μI), and temperature (T). Thereby, the dependence of the critical temperature on isospin chemical potential could be mapped out in the (T−μI) phase diagram. The in-medium modifications of pseudoscalars (Jpc=0−+), scalars (Jpc=0++), vectors (Jpc=1−−), and axial-vectors (Jpc=1++) meson states are then analyzed in thermal and dense medium. We conclude that the QCD phase diagram (T−μI) is qualitatively similar to the (T−μB) phase diagram. We also conclude that both temperature and isospin chemical potential enhance the in-medium modifications of the meson states a0, σ, η′, π, f0, κ, η, K, ρ, ω, κ*, ϕ, a1, f1, K*, and f1*. Regarding their chemical potential, at high temperatures the various meson states likely dissolve into colored partonic phase. In this limit, the meson masses form a universal bundle. Thus, we conclude that the increase in the chemical potential similar to temperature derives the colorless confined meson states into the colored deconfined parton phase.