Using the Schwinger-Keldysh formalism we develop a method for solving self-consistently the Schwinger-Dyson equations for pions and deltas in nuclear medium at nonzero temperature. The vertex corrections are neglected and the nucleon is treated as a mean field. The correct analytic properties of the pions and deltas propagators are assured by using dispersion relations to relate their real and imaginary parts. While the width of the pions spectral function at low momentum increases with increasing temperature, the opposite is true for higher momenta implying that the quasiparticle approximation is a rather good one at high temperature.
ASJC Scopus subject areas
- Nuclear and High Energy Physics