English
Related papers

Related papers: Shear viscosity in neutron star cores

200 papers

We present, for the first time, simultaneous determination of shear viscosity ($\eta$) and entropy density ($s$) and thus, $\eta/s$ for equilibrated nuclear systems from $A$ $\sim$ 30 to $A$ $\sim$ 208 at different temperatures. At finite…

Nuclear multifragmentation in intermediate energy heavy ion collisions has long been associated with liquid-gas phase transition. We calculate the shear viscosity to entropy density ratio eta/s for an equilibrated system of nucleons and…

Nuclear Theory · Physics 2014-11-20 Subrata Pal

We discuss in detail the shear viscosity coefficient eta and the viscosity to entropy density ratio eta/s of a hadronic gas comprised of pions and nucleons. In particular, we study the effects of baryon chemical potential on eta and eta/s.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Kazunori Itakura , Osamu Morimatsu , Hiroshi Otomo

In this work, we have calculated the transport coefficients: shear viscosity and thermal conductivity inside the neutron star core. Our calculation is based on the relativistic kinetic theory approach using a modified BUU equation for…

Nuclear Theory · Physics 2026-03-20 Utsab Gangopadhyaya , Suman Pal , Gargi Chaudhuri

The diffusive thermal conductivity of neutrons in dense matter [$\rho \sim (1 - 8) \times 10^{14}$ g cm$^{-3}$] of neutron star cores is calculated. The contribution from neutron--neutron and neutron--proton collisions is taken into…

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

The correlations of the crust-core transition density and pressure in neutron stars with the slope of the symmetry energy and the neutron skin thickness are investigated, using different families of relativistic mean field parametrizations…

Nuclear Theory · Physics 2016-04-11 H. Pais , A. Sulaksono , B. K. Agrawal , C. Providência

The core of a neutron star contains several species of particles, whose relative equilibrium concentrations are determined by the local density. As the star spins down, its centrifugal force decreases continuously, and the star contracts.…

Astrophysics · Physics 2009-10-22 Andreas Reisenegger

In this talk I report my recent study on the shear viscosity of neutron-rich nuclear matter from a relaxation time approach. An isospin- and momentum-dependent interaction is used in the study. Effects of density, temperature, and isospin…

Nuclear Theory · Physics 2013-12-31 Jun Xu

We review the effective field theory associated with the superfluid phonons that we use for the study of transport properties in the core of superfluid neutrons stars in their low temperature regime. We then discuss the shear and bulk…

Nuclear Theory · Physics 2021-03-08 Cristina Manuel , Laura Tolos

The specific shear viscosity $\bar\eta$ of a classically rotating system of nucleons that interact via a monopole pairing interaction is calculated including the effects of thermal fluctuations and coupling to pair vibrations within the…

Nuclear Theory · Physics 2015-06-05 N. Quang Hung , N. Dinh Dang

The calculation of transport properties of Fermi liquids, based on the formalism developed by Abrikosov and Khalatnikov, requires the knowledge of the probability of collisions between quasiparticles in the vicinity of the Fermi surface. We…

Nuclear Theory · Physics 2008-11-26 Omar Benhar , Marco Valli

Based on IBUU simulations calibrated by previous efforts of the transport model evaluation project, we have studied the specific shear viscosity $\eta/s$ of nuclear matter in the spinodal region using the Green-Kubo method. With the…

Nuclear Theory · Physics 2023-03-03 Lei-Ming Hua , Jun Xu

We calculate thermal conductivity and shear viscosity of nucleons in dense nuclear matter of neutron star cores in the non-relativistic Brueckner-Hartree-Fock framework. Nucleon-nucleon interaction is described by the Argonne v18 potential…

Solar and Stellar Astrophysics · Physics 2015-06-17 P. S. Shternin , M. Baldo , P. Haensel

Bulk viscosity of neutron star cores containing hyperons is studied taking into account non-equilibrium weak process $n+n \rightleftharpoons p+\Sigma^-$. Rapid growth of the bulk viscosity within the neutron star core associated with…

Astrophysics · Physics 2010-02-05 P. Haensel , K. P. Levenfish , D. G. Yakovlev

The Green-Kubo relation and fluctuation-dissipation theorem are employed to calculate the shear viscosity $\eta$ of a finite hot nucleus directly from the width and energy of the giant dipole resonance (GDR) of this nucleus. The ratio…

Nuclear Theory · Physics 2015-05-30 Nguyen Dinh Dang

We present a numerical study of shear viscosity and thermal conductivity of symmetric nuclear matter, pure neutron matter and $\beta$-stable nuclear matter, in the framework of the Brueckner theory. The calculation of in-medium cross…

Solar and Stellar Astrophysics · Physics 2014-11-21 H. F. Zhang , U. Lombardo , W. Zuo

The viscosity of hadronic matter is studied using a classical evaluation of the scattering angle and a quantum mechanical discussion based on phase shifts from a potential. Semi classical limits of the quantum theory are presented. A hard…

Nuclear Theory · Physics 2010-09-30 Aram Z. Mekjian

Recent studies invoke a unified description of different neutron star observables using metamodels, which parametrize the Equation of State (EoS) of neutron star matter close to nuclear saturation density in terms of few nuclear parameters.…

High Energy Physics - Phenomenology · Physics 2026-03-26 José Luis Hernández , Cristina Manuel , Laura Tolos

Neutron stars are expected to contain a significant number of hyperons in addition to protons and neutrons in the highest density portions of their cores. Following the work of Jones, we calculate the coefficient of bulk viscosity due to…

Astrophysics · Physics 2009-11-07 Lee Lindblom , Benjamin J. Owen

Within a Boltzmann transport model, we demonstrate correlation between stopping observables and shear viscosity in central nuclear collisions at intermediate energies (on the order of 10 to 1000 MeV/nucleon). The correlation allows us to…

Nuclear Theory · Physics 2019-03-27 Brent Barker , Pawel Danielewicz