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arXiv · 0803.3257

Quasifermion spectrum at finite temperature from coupled Schwinger-Dyson equations for a fermion-boson system

Masayasu Harada·Yukio Nemoto
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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.

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Masayasu Harada, Yukio Nemoto. 2008-06-30. Quasifermion spectrum at finite temperature from coupled Schwinger-Dyson equations for a fermion-boson system. https://doi.org/10.1103/physrevd.78.014004

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