Fermion Spectrum at Ultrasoft Region in a Hot QED/QCD Plasma

Abstract

An spectrum of an electron (quark) with ultrasoft momentum (p g^2T) is discussed at extremely high temperature in quantum electrodynamics (chromodynamics) with a resummed perturbation theory. We establish the existence of the pole suggested in the previous work of the electron (quark) propagator at ultrasoft region, and find that its pole position is p_0=\mp |p|/3-iζ, where ζis the damping rate which is of order g^2T ln 1/g, and the expression of its residue. We also discuss whether the resummation scheme preserves the gauge symmetry.

3 pages, 1 figure, presented by D. Satow at the 19th Particles and Nuclei International Conference, PANIC 2011, MIT, Cambridge, MA (July 24-29, 2011)