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Title: Shear viscosities of photons in strongly coupled plasmas

Abstract

We investigate the shear viscosity of thermalized photons in the quark gluon plasma (QGP) at weak coupling and N=4 super Yang–Mills plasma (SYMP) at both strong and weak couplings. We find that the shear viscosity due to the photon–parton scattering up to the leading order of electromagnetic coupling is suppressed when the coupling of the QGP/SYMP is increased, which stems from the blue-shift of the thermal-photon spectrum at strong coupling. In addition, the shear viscosity rapidly increases near the deconfinement transition in a phenomenological model analogous to the QGP.

Authors:
 [1];  [2]
  1. RIKEN, Saitama (Japan); Univ. of Crete (Greece)
  2. Duke Univ., Durham, NC (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
OSTI Identifier:
1264789
Report Number(s):
BNL-114741-2017-JA
Journal ID: ISSN 0370-2693; R&D Project: PO3; TRN: US1800353
Grant/Contract Number:
SC0012704; FG02-05ER41367
Resource Type:
Journal Article: Published Article
Journal Name:
Physics Letters. Section B
Additional Journal Information:
Journal Volume: 760; Journal Issue: C; Journal ID: ISSN 0370-2693
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

Citation Formats

Yang, Di-Lun, and Müller, Berndt. Shear viscosities of photons in strongly coupled plasmas. United States: N. p., 2016. Web. doi:10.1016/j.physletb.2016.07.034.
Yang, Di-Lun, & Müller, Berndt. Shear viscosities of photons in strongly coupled plasmas. United States. doi:10.1016/j.physletb.2016.07.034.
Yang, Di-Lun, and Müller, Berndt. 2016. "Shear viscosities of photons in strongly coupled plasmas". United States. doi:10.1016/j.physletb.2016.07.034.
@article{osti_1264789,
title = {Shear viscosities of photons in strongly coupled plasmas},
author = {Yang, Di-Lun and Müller, Berndt},
abstractNote = {We investigate the shear viscosity of thermalized photons in the quark gluon plasma (QGP) at weak coupling and N=4 super Yang–Mills plasma (SYMP) at both strong and weak couplings. We find that the shear viscosity due to the photon–parton scattering up to the leading order of electromagnetic coupling is suppressed when the coupling of the QGP/SYMP is increased, which stems from the blue-shift of the thermal-photon spectrum at strong coupling. In addition, the shear viscosity rapidly increases near the deconfinement transition in a phenomenological model analogous to the QGP.},
doi = {10.1016/j.physletb.2016.07.034},
journal = {Physics Letters. Section B},
number = C,
volume = 760,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.physletb.2016.07.034

Citation Metrics:
Cited by: 1work
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  • We investigate the shear viscosity of thermalized photons in the quark gluon plasma (QGP) at weak coupling and N=4 super Yang–Mills plasma (SYMP) at both strong and weak couplings. We find that the shear viscosity due to the photon–parton scattering up to the leading order of electromagnetic coupling is suppressed when the coupling of the QGP/SYMP is increased, which stems from the blue-shift of the thermal-photon spectrum at strong coupling. In addition, the shear viscosity rapidly increases near the deconfinement transition in a phenomenological model analogous to the QGP.
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  • We present an approximation to the linearized collision operator or memory function of the exact kinetic equation obeyed by the correlation function of the phase-space density of a classical one-component plasma. This approximate collision operator generalizes the well known Balescu-Guernsey-Lenard (BGL) operator to finite wavelengths, finite frequencies, and finite coupling constants. It, moreover, satisfies the necessary symmetry relations, leads to appropriate conservation laws, and fulfills its first sum rule exactly. Next we use this operator to compute the shear viscosity eta for a series of coupling constants spanning the whole fluid phase. For weak coupling we make contact with themore » BGL theory, while for strong coupling we confirm, at least qualitatively, the results of Vieillefosse and Hansen, who predicted a minimum in eta as a function of temperature. We also demonstrate the important role played by the sum rules in the quantitative evaluation of a transport coefficient such as eta.« less
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