Quasifermion spectrum at finite temperature from coupled Schwinger-Dyson equations for a fermion-boson system
arXiv:0803.3257 · doi:10.1103/PhysRevD.78.014004
Abstract
We nonperturbatively investigate a fermion spectrum at finite temperature in a chiral invariant linear sigma model. Coupled Schwinger-Dyson equations for fermion and boson are developed in the real time formalism and solved numerically. From the coupling of a massless fermion with a massive boson, the fermion spectrum shows a three-peak structure at some temperatures even for the strong coupling region. This means that the three-peak structure which was originally found in the one-loop calculation is stable against higher order corrections even in the strong coupling region.
10 pages, 10 figures, minor changes on discussion on renormalization, typos corrected, version to appear in Phys. Rev. D