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Related papers: Bulk viscosity of superfluid hyperon stars

200 papers

A microscopic, quantum mechanical model for neutron vortices in the crust of a neutron star is presented. After a brief introduction to the Bogoliubov- de Gennes equations, which form the basis for our calculations, we present results for…

Astrophysics · Physics 2009-11-06 O. Elgaroy , F. V. De Blasio

We calculate the superfluid density of nucleons in disordered pasta phases in the inner crust of neutron stars using an effective medium approach which parallels that previously used for calculating the electrical conductivity of…

Nuclear Theory · Physics 2022-06-01 Zhao-Wen Zhang , C. J. Pethick

For treatment of the layers below the crust of a neutron star it is useful to employ a relativistic model involving three independently moving constituents, representing superfluid neutrons, superfluid protons, and degenerate negatively…

Astrophysics · Physics 2007-05-23 Brandon Carter

We discuss a new superfluid instability occuring in the interior of mature neutron stars with implications for freely precessing neutron stars. This short-wavelength instability is similar to the instability which is responsible for the…

Astrophysics · Physics 2008-11-26 K. Glampedakis , N. Andersson , D. I. Jones

In this paper, we discuss the damping of density oscillations in dense nuclear matter in the temperature range relevant to neutron star mergers. This damping is due to bulk viscosity arising from the weak interaction ``Urca'' processes of…

Nuclear Theory · Physics 2020-06-23 Mark Alford , Arus Harutyunyan , Armen Sedrakian

Nuclear superfludity in exotic nuclei close to the drip lines and in the inner crust matter of neutron stars have common features which can be treated with the same theoretical tools. In the first part of my lecture I discuss how two such…

Nuclear Theory · Physics 2017-08-23 Nicolae Sandulescu

We formulate dissipative magnetohydrodynamic equations for finite-temperature superfluid and superconducting charged relativistic mixtures, taking into account the effects of particle diffusion and possible presence of Feynman-Onsager…

High Energy Astrophysical Phenomena · Physics 2021-12-15 Vasiliy A. Dommes , Mikhail E. Gusakov

This article starts by providing an introductory overview of the theoretical mechanics of rotating neutron stars as developped to account for the frequency variations, and particularly the discontinuous glitches, observed in pulsars. The…

Astrophysics · Physics 2007-05-23 Brandon Carter

We present a general formalism to treat slowly rotating general relativistic superfluid neutron stars. As a first approximation, their matter content can be described in terms of a two-fluid model, where one fluid is the neutron superfluid,…

General Relativity and Quantum Cosmology · Physics 2009-10-31 N. Andersson , G. L. Comer

We study bulk viscosity arising from weak current Urca processes in dense baryonic matter at and beyond nuclear saturation density. We consider the temperature regime where neutrinos are trapped and therefore have nonzero chemical…

High Energy Astrophysical Phenomena · Physics 2019-11-27 Mark Alford , Arus Harutyunyan , Armen Sedrakian

We consider transport properties of the hypernuclear matter in neutron star cores. In particular, we calculate the thermal conductivity, the shear viscosity, and the momentum transfer rates for np$\Sigma^{-}\Lambda e\mu$ composition of…

High Energy Astrophysical Phenomena · Physics 2021-06-24 Peter Shternin , Isaac Vidaña

A general formalism for calculating the bulk viscosity of strange quark matter is developed. Contrary to the common belief that the non-leptonic processes alone give the dominant contribution to the bulk viscosity, the inclusion of the Urca…

Astrophysics · Physics 2008-11-26 Basil A. Sa'd , Igor A. Shovkovy , Dirk H. Rischke

This work is concerned with advancing multi-fluid models in General Relativity, and in particular focuses on the modelling of dissipative fluids and turbulent flows. Such models are required for an accurate description of neutron star…

High Energy Astrophysical Phenomena · Physics 2023-07-13 Thomas Celora

Bulk viscosity is an important transport coefficient that exists in the hydrodynamical limit only when the underlying theory is non-conformal. One example being thermal QCD with large number of colors. We study bulk viscosity in such a…

High Energy Physics - Theory · Physics 2018-07-23 Alina Czajka , Keshav Dasgupta , Charles Gale , Sangyong Jeon , Aalok Misra , Michael Richard , Karunava Sil

Cooling simulations of neutron stars (NSs) are performed assuming that stellar cores consist of neutrons, protons and electrons and using realistic density profiles of superfluid critical temperatures $T_{cn}(\rho)$ and $T_{cp}(\rho)$ of…

Astrophysics · Physics 2009-11-06 A. D. Kaminker , P. Haensel , D. G. Yakovlev

The dynamics of a neutron star after a glitch involve the transfer of angular momentum from the crust (where the glitch is presumed to originate) to the liquid core, causing the core to spin up. The crust-core coupling, which determines how…

High Energy Astrophysical Phenomena · Physics 2024-10-21 J. R. Fuentes , Vanessa Graber

We compute the contribution of phonons to the shear viscosity $\eta$ in superfluid neutron stars, assuming neutron pairing in a $^1S_0$ channel. We use a Boltzmann equation amended by a collision term that takes into account the binary…

Solar and Stellar Astrophysics · Physics 2013-05-29 Cristina Manuel , Laura Tolos

We study the bulk viscosity of dense matter, taking into account non-linear effects which arise in the large amplitude "supra-thermal" region where the deviation $\mu_\Delta$ of the chemical potentials from chemical equilibrium fulfills…

Nuclear Theory · Physics 2011-03-28 Mark G. Alford , Simin Mahmoodifar , Kai Schwenzer

We calculate the shear viscosity $\eta = \eta_{e\mu}+\eta_{n}$ in a neutron star core composed of nucleons, electrons and muons ($\eta_{e\mu}$ being the electron-muon viscosity, mediated by collisions of electrons and muons with charged…

Astrophysics · Physics 2009-02-20 P. S. Shternin , D. G. Yakovlev

Hydro-kinetic theory of thermal fluctuations is applied to a non-conformal relativistic fluid. Solving the hydro-kinetic equations for an isotropically expanding background we find that hydrodynamic fluctuations give ultraviolet divergent…

Nuclear Theory · Physics 2018-08-21 Yukinao Akamatsu , Aleksas Mazeliauskas , Derek Teaney