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Related papers: Bulk viscosity of superfluid hyperon stars

200 papers

We present a geometrical derivation of the relativistic dynamics of the superfluid inner crust of a neutron star. The resulting model is analogous to the Hall-Vinen-Bekarevich-Khalatnikov hydrodynamics for a single-component superfluid at…

High Energy Astrophysical Phenomena · Physics 2021-02-23 Lorenzo Gavassino , Marco Antonelli , Brynmor Haskell

As a neutron star spins down, the gradual decrease of the centrifugal force produces a progressive increase of the density of any given fluid element in its interior. Since the ``chemical'' (or ``beta'') equilibrium state is determined by…

Astrophysics · Physics 2009-10-28 Andreas Reisenegger

We investigate the tidal deformability of a superfluid neutron star. We calculate the equilibrium structure in the general relativistic two-fluid formalism with entrainment effect where we take neutron superfluid as one fluid and the other…

General Relativity and Quantum Cosmology · Physics 2018-10-10 Prasanta Char , Sayak Datta

Baryon and quark superfluidity in the cooling of neutron stars are investigated. Observations could constrain combinations of the neutron or Lambda-hyperon pairing gaps and the star's mass. However, in a hybrid star with a mixed phase of…

High Energy Physics - Phenomenology · Physics 2011-05-05 Dany Page , Madappa Prakash , James M. Lattimer , Andrew Steiner

Neutron-star cores may be hosts of a unique mixture of a neutron superfluid and a proton superconductor. Compelling theoretical arguments have been presented over the years that if the proton superconductor is of type II, than the…

Astrophysics · Physics 2009-11-13 Maarten van Hoven , Yuri Levin

We investigate the influence of nucleon superfluidity on the neutrino emissivity of non-equilibrium beta processes. Calculations are performed of the reduction factors for direct and modified Urca processes with three types of nucleon…

High Energy Astrophysical Phenomena · Physics 2011-09-14 Chun-Mei Pi , Xiao-Ping Zheng , Shu-Hua Yang

We investigate the shear viscosity of neutron star matter in the presence of an antikaon condensate. The electron and muon number densities are reduced due to the appearance of a $K^-$ condensate in neutron star matter, whereas the proton…

Solar and Stellar Astrophysics · Physics 2010-04-23 Rana Nandi , Sarmistha Banik , Debades Bandyopadhyay

We evaluate the three bulk viscosity coefficients $\zeta_1, \zeta_2$ and $\zeta_3$ in the color-flavor locked (CFL) superfluid phase due to phonons and kaons, which are the lightest modes in that system. We first show that the computation…

High Energy Physics - Phenomenology · Physics 2011-08-08 Robert Bierkandt , Cristina Manuel

We use a Bayesian-calibrated multistage viscous hydrodynamic model to explore deuteron yield, mean transverse momentum and flow observables in LHC Pb-Pb collisions. We explore theoretical uncertainty in the production of deuterons,…

We study the effect of superfluidity on the tidal response of a neutron star in a general relativistic framework. In this work, we take a dual-layer approach where the superfluid matter is confined in the core of the star. Then, the…

General Relativity and Quantum Cosmology · Physics 2020-09-16 Sayak Datta , Prasanta Char

We study the effect of magnetic field on the bulk viscosity of nuclear matter in neutron stars. We employ the framework of relativistic mean field theory to observe the dense nuclear matter in neutron stars. The effects are first studied…

Astrophysics · Physics 2008-11-26 J D Anand , V K Gupta , Ashok Goyal , S Singh , Kanupriya Goswami

The specific viscosity of neutron-rich nuclear matter is studied from the relaxation time approach using an isospin- and momentum-dependent interaction and the nucleon-nucleon cross sections taken as those from the experimental data…

Nuclear Theory · Physics 2011-12-06 Jun Xu

A mixture of superconducting and superfluid nuclear liquids of protons coupled to the ultrarelativistic electron gas, and neutrons is considered. In the magnetohydrodynamic (MHD) approximation, the energy-momentum (stress) tensor is…

Nuclear Theory · Physics 2018-10-19 D. N. Kobyakov

Despite the absence of viscous drag, the neutron superfluid permeating the inner crust of a neutron star can still be strongly coupled to nuclei due to non-dissipative entrainment effects. Neutron superfluidity and entrainment have been…

High Energy Astrophysical Phenomena · Physics 2012-07-02 N. Chamel , J. M. Pearson , S. Goriely

We study the superfluid dynamics of the outer core of neutron stars by means of a hydrodynamic model made of a neutronic superfluid and a protonic superconductor, coupled by both the dynamic entrainment and the Skyrme SLy4 nucleon-nucleon…

Nuclear Theory · Physics 2021-06-23 J. A. Gil Granados , A. Muñoz Mateo , X. Viñas

Neutron stars are believed to contain (neutron and proton) superfluids. I will give a summary of a macroscopic description of the interior of neutron stars, in a formulation which is general relativistic. I will also present recent results…

General Relativity and Quantum Cosmology · Physics 2017-08-23 David Langlois

Using time evolutions of the relevant linearised equations we study non-axisymmetric oscillations of rapidly rotating and superfluid neutron stars. We consider perturbations of Newtonian axisymmetric background configurations and account…

Astrophysics · Physics 2009-11-13 Andrea Passamonti , Brynmor Haskell , Nils Andersson

We examine bulk viscosity, taking into account trapped neutrinos in baryonic matter, in the context of binary neutron star mergers. Following the merging event, the binary star can yield a remnant compact object with densities up to $5$…

Nuclear Theory · Physics 2024-09-25 Sreemoyee Sarkar , Rana Nandi

We survey the current status of understanding of pairing and superfluidity of neutrons and protons in neutron stars from a theoretical perspective, with emphasis on basic physical properties. During the past two decades, the blossoming of…

Nuclear Theory · Physics 2015-04-15 A. Gezerlis , C. J. Pethick , A. Schwenk

High surface density, rapidly star-forming galaxies are observed to have $\approx 50-100\,{\rm km\,s^{-1}}$ line-of-sight velocity dispersions, which are much higher than expected from supernova driving alone, but may arise from large-scale…

Astrophysics of Galaxies · Physics 2016-02-17 Sharanya Sur , Evan Scannapieco , Eve C. Ostriker