Aleksandr Dubinin

Pion and sigma meson dissociation and modified PNJL model at finite temperature

We investigate the thermodynamics of two-particle correlations in a hot medium, with correlations in the pion, sigma meson interaction channels. Special emphasis is put on a correct description of the bound states’ dissociation in the vicinity and beyond the Mott temperature. This is achieved by evaluating the polarization functions for quark-antiquark (meson) correlations as a function of the temperature. The results can be represented by introducing modulus and phase of the complex propagator functions for these states. We study the effect of modeling confinement by a low-momentum cutoff in loop integrals on the behavior of the phase shifts. On this basis the thermodynamical potential and the equation of state for quark matter with meson correlations is evaluated in analogy to a Beth-Uhlenbeck equation.