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Related papers: Shear viscosity in neutron star cores

200 papers

The ratio of the shear viscosity ($\eta$) to entropy density ($s$) for the intermediate energy heavy-ion collisions has been calculated by using the Green-Kubo method in the framework of the quantum molecular dynamics model. The theoretical…

Nuclear Theory · Physics 2012-06-29 C. L. Zhou , Y. G. Ma , D. Q. Fang , S. X. Li , G. Q. Zhang

Equilibration of highly excited baryon-rich matter is studied within the microscopic model calculations in A+A collisions at energies of BES, FAIR and NICA. It is shown that the system evolution from the very beginning of the collision can…

Nuclear Theory · Physics 2021-02-03 E. Zabrodin , L. Bravina , M. Teslyk , O. Vitiuk

Several different processes could be changing the density in the core of a neutron star, leading to a departure from $\beta$ equilibrium, quantified by the chemical potential difference $\delta\mu\equiv\mu_n-\mu_p-\mu_e$. The evolution of…

Astrophysics · Physics 2009-11-11 Sergio Flores-Tulian , Andreas Reisenegger

Shear $\eta$ and bulk $\zeta$ viscosities are calculated in a quasiparticle model within a relaxation time approximation for pure gluon matter. Below $T_c$ the confined sector is described within a quasiparticle glueball model. Particular…

Nuclear Theory · Physics 2015-03-17 A. S. Khvorostukhin , V. D. Toneev , D. N. Voskresensky

The shear viscosity of hot nuclear matter is investigated by using the mean free path method within the framework of IQMD model. Finite size nuclear sources at different density and temperature are initialized based on the Fermi-Dirac…

Nuclear Theory · Physics 2014-04-29 D. Q. Fang , Y. G. Ma , C. L. Zhou

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

The Rossby mode (r-mode) perturbation in pulsars as a steady gravitational wave (GW) source has been explored. The effect of a rigid crust on viscous damping and dissipation rate in the boundary layer between fluid core and crust has been…

Nuclear Theory · Physics 2025-02-24 Debasis Atta , D. N. Basu

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

With various sets of the parameters that characterize the equation of state (EOS) of nuclear matter, we systematically examine the thickness of a neutron star crust and of the pasta phases contained therein. Then, with respect to the…

High Energy Astrophysical Phenomena · Physics 2017-08-02 Hajime Sotani , Kei Iida , Kazuhiro Oyamatsu

We demonstrate that observations of glitches in the Vela pulsar can be used to investigate the strength of the crust-core coupling in a neutron star, and suggest that recovery from the glitch is dominated by torque exerted by the…

Solar and Stellar Astrophysics · Physics 2015-11-04 William G. Newton , Sabrina Berger , Brynmor Haskell

The effects of the existence of exotic nuclear shapes at the bottom of the neutron star inner crust - nuclear `pasta' - on observational phenomena are estimated by comparing the limiting cases that those phases have a vanishing shear…

Solar and Stellar Astrophysics · Physics 2015-05-28 M. Gearheart , W. G. Newton , J. Hooker , Bao-An Li

We evaluate the viscous damping of anisotropic flow in heavy-ion collisions for arbitrary temperature-dependent shear and bulk viscosities. We show that the damping is solely determined by effective shear and bulk viscosities, which are…

Nuclear Theory · Physics 2021-04-29 Fernando G. Gardim , Jean-Yves Ollitrault

We study the diversities in the properties of the neutron stars arising due to the different choices for the cross-coupling between various mesons which governs the density dependence of the nuclear symmetry energy in the extended…

Nuclear Theory · Physics 2018-07-25 N. Alam , A. Sulaksono , B. K. Agrawal

Calculations are performed of the cooling of neutron stars with standard and enhanced neutrino energy losses in the presence of neutron and proton superfluidities in the stellar cores. The effects of superfluidity on the heat capacity and…

Astrophysics · Physics 2007-05-23 K. P. Levenfish , D. G. Yakovlev

We perform a systematic assessment of models for the equation of state (EOS) of dense matter in the context of recent neutron star mass and radius measurements to obtain a broad picture of the structure of neutron stars. We demonstrate that…

Nuclear Theory · Physics 2015-01-27 Andrew W. Steiner , Stefano Gandolfi , Farrukh J. Fattoyev , William G. Newton

Inferring the properties of dense matter is one of the most exciting prospects from the measurement of gravitational waves from neutron star mergers. However, it will require reliable numerical simulations that incorporate viscous…

General Relativity and Quantum Cosmology · Physics 2018-01-31 Mark G. Alford , Luke Bovard , Matthias Hanauske , Luciano Rezzolla , Kai Schwenzer

The shear viscosity $\eta$ in the van der Waals excluded volume hadron-resonance gas model is considered. For the shear viscosity the result of the non-relativistic gas of hard-core particles is extended to the mixture of particles with…

Nuclear Theory · Physics 2011-12-06 M. I. Gorenstein , M. Hauer , O. N. Moroz

Using the relativistic mean-field model with nonlinear couplings between the isoscalar and isovector mesons, we study the properties of isospin-asymmetric nuclear matter. Not only the vector mixing,…

Nuclear Theory · Physics 2022-04-18 Tsuyoshi Miyatsu , Myung-Ki Cheoun , Koichi Saito

A number of properties of dense matter can be understood semiquantitatively in terms of simple physical arguments. We begin with the outer parts of neutron stars, and consider the density at which pressure ionization occurs, the density at…

Nuclear Theory · Physics 2020-03-18 C. J. Pethick

We analyze the effects of including $\Delta(1232)$ isobars in an equation of state (EoS) for cold, $\beta$-stable neutron star matter, employing relativistic nuclear mean field theory. The selected EoS reproduces the properties of nuclear…

High Energy Astrophysical Phenomena · Physics 2019-10-09 Patricia Ribes , Angels Ramos , Laura Tolos , Claudia Gonzalez-Boquera , Mario Centelles