Transport coefficients in superfluid neutron stars
Abstract
We study the shear and bulk viscosity coefficients as well as the thermal conductivity as arising from the collisions among phonons in superfluid neutron stars. We use effective field theory techniques to extract the allowed phonon collisional processes, written as a function of the equation of state and the gap of the system. The shear viscosity due to phonon scattering is compared to calculations of that coming from electron collisions. We also comment on the possible consequences for rmode damping in superfluid neutron stars. Moreover, we find that phonon collisions give the leading contribution to the bulk viscosities in the core of the neutron stars. We finally obtain a temperatureindependent thermal conductivity from phonon collisions and compare it with the electronmuon thermal conductivity in superfluid neutron stars.
 Authors:
 Instituto de Ciencias del Espacio (IEEC/CSIC) Campus Universitat Autònoma de Barcelona, Facultat de Ciències, Torre C5, E08193 Bellaterra (Barcelona) (Spain)
 (Germany)
 Tata Institute of Fundamental Research, Homi Bhaba Road, Mumbai400005 (India)
 Physik Department, Technische Universität München, D85748 Garching (Germany)
 Publication Date:
 OSTI Identifier:
 22499078
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: AIP Conference Proceedings; Journal Volume: 1701; Journal Issue: 1; Conference: 11. conference on quark confinement and hadron spectrum, Saint Petersburg (Russian Federation), 812 Sep 2014; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPARATIVE EVALUATIONS; DAMPING; ELECTRON COLLISIONS; ELECTRONS; EQUATIONS OF STATE; FIELD THEORIES; MUONS; NEUTRON STARS; PHONONS; SCATTERING; SHEAR; SUPERFLUIDITY; THERMAL CONDUCTIVITY; VISCOSITY
Citation Formats
Tolos, Laura, Frankfurt Institute for Advances Studies. Johann Wolfgang Goethe University, RuthMoufangStr. 1, 60438 Frankfurt am Main, Manuel, Cristina, Sarkar, Sreemoyee, and Tarrus, Jaume. Transport coefficients in superfluid neutron stars. United States: N. p., 2016.
Web. doi:10.1063/1.4938690.
Tolos, Laura, Frankfurt Institute for Advances Studies. Johann Wolfgang Goethe University, RuthMoufangStr. 1, 60438 Frankfurt am Main, Manuel, Cristina, Sarkar, Sreemoyee, & Tarrus, Jaume. Transport coefficients in superfluid neutron stars. United States. doi:10.1063/1.4938690.
Tolos, Laura, Frankfurt Institute for Advances Studies. Johann Wolfgang Goethe University, RuthMoufangStr. 1, 60438 Frankfurt am Main, Manuel, Cristina, Sarkar, Sreemoyee, and Tarrus, Jaume. 2016.
"Transport coefficients in superfluid neutron stars". United States.
doi:10.1063/1.4938690.
@article{osti_22499078,
title = {Transport coefficients in superfluid neutron stars},
author = {Tolos, Laura and Frankfurt Institute for Advances Studies. Johann Wolfgang Goethe University, RuthMoufangStr. 1, 60438 Frankfurt am Main and Manuel, Cristina and Sarkar, Sreemoyee and Tarrus, Jaume},
abstractNote = {We study the shear and bulk viscosity coefficients as well as the thermal conductivity as arising from the collisions among phonons in superfluid neutron stars. We use effective field theory techniques to extract the allowed phonon collisional processes, written as a function of the equation of state and the gap of the system. The shear viscosity due to phonon scattering is compared to calculations of that coming from electron collisions. We also comment on the possible consequences for rmode damping in superfluid neutron stars. Moreover, we find that phonon collisions give the leading contribution to the bulk viscosities in the core of the neutron stars. We finally obtain a temperatureindependent thermal conductivity from phonon collisions and compare it with the electronmuon thermal conductivity in superfluid neutron stars.},
doi = {10.1063/1.4938690},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1701,
place = {United States},
year = 2016,
month = 1
}

We calculate the three bulk viscosity coefficients as arising from the collisions among phonons in superfluid neutron stars. We use effective field theory techniques to extract the allowed phonon collisional processes, written as a function of the equation of state of the system. The solution of the dynamical evolution of the phonon number density allows us to calculate the bulk viscosity coefficients as function of the phonon collisional rate and the phonon dispersion law, which depends on the neutron pairing gap. Our method of computation is rather general, and could be used for different superfluid systems, provided they share themore »

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