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Title: Soft fermion dispersion relation at next-to-leading order in hot QED

Abstract

We study next-to-leading-order contributions to the soft static fermion dispersion relation in hot QED. We derive an expression for the complete next-to-leading-order contribution to the retarded fermion self-energy. The real and imaginary parts of this expression give the next-to-leading-order contributions to the mass and damping rate of the fermionic quasiparticle. Many of the terms that are expected to contribute according to the traditional power counting argument are actually subleading. We explain why the power counting method over estimates the contribution from these terms. For the electron damping rate in QED we obtain: {gamma}{sub QED}=(e{sup 2}T/4{pi})(2.70). We check our method by calculating the next-to-leading-order contribution to the damping rate for the case of QCD with two flavors and three colors. Our result agrees with the result obtained previously in the literature. The numerical evaluation of the nlo contribution to the mass is left to a future publication.

Authors:
 [1]
  1. Department of Physics, Brandon University, Brandon, Manitoba, R7A 6A9 Canada and Winnipeg Institute for Theoretical Physics, Winnipeg, Manitoba (Canada)
Publication Date:
OSTI Identifier:
21011112
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.75.045019; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COLOR MODEL; DISPERSION RELATIONS; ELECTRONS; EVALUATION; FLAVOR MODEL; QUANTUM CHROMODYNAMICS; QUANTUM ELECTRODYNAMICS; SELF-ENERGY

Citation Formats

Carrington, M. E.. Soft fermion dispersion relation at next-to-leading order in hot QED. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.045019.
Carrington, M. E.. Soft fermion dispersion relation at next-to-leading order in hot QED. United States. doi:10.1103/PHYSREVD.75.045019.
Carrington, M. E.. Thu . "Soft fermion dispersion relation at next-to-leading order in hot QED". United States. doi:10.1103/PHYSREVD.75.045019.
@article{osti_21011112,
title = {Soft fermion dispersion relation at next-to-leading order in hot QED},
author = {Carrington, M. E.},
abstractNote = {We study next-to-leading-order contributions to the soft static fermion dispersion relation in hot QED. We derive an expression for the complete next-to-leading-order contribution to the retarded fermion self-energy. The real and imaginary parts of this expression give the next-to-leading-order contributions to the mass and damping rate of the fermionic quasiparticle. Many of the terms that are expected to contribute according to the traditional power counting argument are actually subleading. We explain why the power counting method over estimates the contribution from these terms. For the electron damping rate in QED we obtain: {gamma}{sub QED}=(e{sup 2}T/4{pi})(2.70). We check our method by calculating the next-to-leading-order contribution to the damping rate for the case of QCD with two flavors and three colors. Our result agrees with the result obtained previously in the literature. The numerical evaluation of the nlo contribution to the mass is left to a future publication.},
doi = {10.1103/PHYSREVD.75.045019},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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