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Related papers: Shear viscosity in neutron star cores

200 papers

We investigate the temperature dependence of the shear viscosity to entropy density ratio $\eta/s$ using a piecewise linear parametrization. To determine the optimal values of the parameters and the associated uncertainties, we perform a…

The crust of a neutron star is known to melt at a temperature that increases with increasing matter density, up to about $10^{10}$ K. At such high temperatures and beyond, the crustal ions are put into collective motion and the associated…

High Energy Astrophysical Phenomena · Physics 2023-09-06 H. Dinh Thi , A. F. Fantina , F. Gulminelli

The ratio eta/s, shear viscosity (eta) to entropy density (s), reaches its local minimum at the (second order) phase transition temperature in a wide class of systems. It was suspected that this behavior might be universal. However, a…

High Energy Physics - Phenomenology · Physics 2011-06-28 Jiunn-Wei Chen , Chang-Tse Hsieh , Han-Hsin Lin

The neutron density distributions and neutron skin thicknesses in $^{40,48}$Ca are determined from the angular distributions of the cross sections and analyzing powers of polarized proton elastic scattering at $E_p = 295$ MeV. Based on the…

I calculate the rate of electromagnetic scattering in degenerate and partially degenerate plasmas composed of electrons, muons, protons, and neutrons. Correlations with strong interactions, induced by the polarizability of…

Nuclear Theory · Physics 2019-03-01 Stephan Stetina

We calculate the coefficient of bulk viscosity by considering the non-leptonic weak interactions in the cores of hybrid stars with both hyperons and quarks. We first determine the dependence of the production rate of neutrons on the…

Astrophysics · Physics 2009-11-11 Nana Pan , Xiaoping Zheng , Jiarong Li

Hydrodynamic simulations of neutron star mergers rely on the clear separation between the strong-interaction, weak-interaction, and hydrodynamic timescales. In this effective framework, weak Urca interactions are typically the slowest…

High Energy Astrophysical Phenomena · Physics 2026-03-17 Jamie M. Karthein , Maneesha Sushama Pradeep , Rachel Steinhorst

Based on the gravitational collapse time-scale is larger than the weak interaction time-scale at core densities $\rho > 10^{11} {gr}/ {cm}^{3}$, we approximately use the $\beta$-equilibrium condition and particle number conservations to…

High Energy Astrophysical Phenomena · Physics 2012-06-05 R. Mohammadi , Remo Ruffini , She-Sheng Xue

A method is presented to extract the neutron-skin thickness of atomic nuclei from the second and fourth moments of the electric charge distribution. We show that the value of the proton fourth moment must be independently known in order to…

Nuclear Theory · Physics 2021-08-11 Tomoya Naito , Gianluca Colò , Haozhao Liang , Xavier Roca-Maza

We present some results about a novel damping mechanism of r-mode oscillations in neutron stars due to processes that change the number of protons, neutrons and electrons. Deviations from equilibrium of the number densities of the various…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Massimo Mannarelli , Giuseppe Colucci , Cristina Manuel

Neutrino emission from the dense hadronic component in neutron stars is subject to strong modifications due to collective effects in the nuclear medium. We implement new estimates of the neutrino emissivities of two processes operating in…

Astrophysics · Physics 2011-05-23 Ch. Schaab , D. Voskresensky , A. D. Sedrakian , F. Weber , M. K. Weigel

The knowledge of the nuclear symmetry energy of hot neutron-rich matter is important for understanding the dynamical evolution of massive stars and the supernova explosion mechanisms. In particular, the electron capture rate on nuclei…

Nuclear Theory · Physics 2008-11-26 Ch. C. Moustakidis

The presence of a viscous boundary layer under the solid crust of a neutron star dramatically increases the viscous damping rate of the fluid r-modes. We improve previous estimates of this damping rate by including the effect of the…

Astrophysics · Physics 2009-10-31 Lee Lindblom , Benjamin J. Owen , Greg Ushomirsky

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 model dependence and the symmetry energy dependence of the core-crust transition properties for the neutron stars are studied using three different families of systematically varied extended relativistic mean field model. Several forces…

Nuclear Theory · Physics 2015-06-23 A. Sulaksono , Naosad Alam , B. K. Agrawal

In dense stellar environments, nuclei may become unstable against electron captures and/or neutron emissions. These processes are of particular importance for determining the internal constitution of white-dwarf cores and neutron-star…

Nuclear Theory · Physics 2021-03-11 Nicolas Chamel , Anthea Fantina

{\it Background.} We investigate possible correlations between neutron star observables and properties of atomic nuclei. Particularly, we explore how the tidal deformability of a 1.4 solar mass neutron star, $M_{1.4}$, and the neutron skin…

Nuclear Theory · Physics 2021-02-17 G. F. Burgio , I. Vidana

A symmetry-preserving Dyson-Schwinger equation treatment of a vector-vector contact interaction is used to compute dressed-quark-core contributions to the nucleon $\sigma$-term and tensor charges. The latter enable one to directly determine…

Nuclear Theory · Physics 2015-04-08 Mario Pitschmann , Chien-Yeah Seng , Craig D. Roberts , Sebastian M. Schmidt

It has been shown recently that taking into account strong, weak, electromagnetic, and gravitational interactions, and fulfilling the global charge neutrality of the system, a transition layer will happen between the core and crust of…

Solar and Stellar Astrophysics · Physics 2014-03-20 Jorge A. Rueda , Remo Ruffini , Yuan-Bin Wu , She-Sheng Xue

In this paper we present a computation of the rates of strangeness-changing processes and the resultant bulk viscosity in matter at the densities and temperatures typical of neutron star mergers. To deal with the high temperature in this…

Nuclear Theory · Physics 2021-05-05 Mark G. Alford , Alexander Haber