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Related papers: Bulk Viscosity in Neutron Stars from Hyperons

200 papers

Bulk viscosity may serve to damp sound waves in a system of neutrinos coupled to very light scalar particles, in the era after normal neutrino decoupling but before recombination. We calculate the bulk viscosity parameter in a minimal…

Astrophysics · Physics 2009-11-11 R. F. Sawyer

Recent progress in the understanding of the high density phase of neutron stars advances the view that a substantial fraction of the matter consists of hyperons. The possible impacts of a highly attractive interaction between hyperons on…

Astrophysics · Physics 2009-10-31 Jurgen Schaffner-Bielich , Matthias Hanauske , Horst Stocker , Walter Greiner

The theoretical status of the hyperon-nucleon and hyperon-hyperon interactions is reviewed, paying a special attention to chiral effective field theories. Results on hyperons in dense matter are presented and the consequences for the…

Nuclear Theory · Physics 2020-10-08 Laura Tolos

Neutrino processes in dense matter play a key role in the dynamics, deleptonization and early cooling of hot protoneutron stars formed in the gravitational collapse of massive stars. Here we calculate neutrino mean free paths from…

Nuclear Theory · Physics 2009-09-25 Sanjay Reddy , Madappa Prakash

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

By employing a recently constructed hyperon-nucleon potential the equation of state of \beta-equilibrated and charge neutral nucleonic matter is calculated. The hyperon-nucleon potential is a low-momentum potential which is obtained within…

Nuclear Theory · Physics 2014-11-18 Haris Djapo , Bernd-Jochen Schaefer , Jochen Wambach

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

Recent astrophysical observations of neutron stars and heavy-ion data are confronted with our present understanding of the equation of state of dense hadronic matter. Emphasis is put on the possible role of the presence of hyperons in the…

Astrophysics · Physics 2007-11-16 Irina Sagert , Mirjam Wietoska , Jurgen Schaffner-Bielich , Christian Sturm

We discuss the effects induced by the potential presence of hyperons in hot and ultra-dense matter within the context of neutron star mergers. Specifically, we address their effect on the dominant post-merger frequency of the gravitational…

High Energy Physics - Phenomenology · Physics 2024-11-25 Hristijan Kochankovski , Angels Ramos , Laura Tolos , Sebastian Blacker , Andreas Bauswein

Available Skyrme parametrizations with hyperons are examined from the point of view of their suitability for applications to neutron stars. It is shown that the hyperons can attenuate or even remove the problem of ferromagnetic instability…

Nuclear Theory · Physics 2009-11-10 L. Mornas

The phonon contribution to the shear viscosity $\eta$ in superfluid neutron stars is calculated by assuming neutron pairing in a $^1S_0$ channel. The shear viscosity is obtained by means of variational methods for the solution of the…

High Energy Astrophysical Phenomena · Physics 2012-06-19 Laura Tolos , Cristina Manuel

We study the charged and neutral current weak interaction rates relevant for the determination of neutrino opacities in dense matter found in supernovae and neutron stars. We establish an efficient formalism for calculating differential…

Astrophysics · Physics 2010-04-06 Sanjay Reddy , Madappa Prakash , James M Lattimer

We study the role of pions in hot dense matter encountered in astrophysics. We find that strong interactions enhance the number density of negatively charged pions and that this enhancement can be calculated reliably for a relevant range of…

High Energy Astrophysical Phenomena · Physics 2020-04-08 Bryce Fore , Sanjay Reddy

The influence of the presence of hyperons in dense hadronic matter on the quantum nucleation of quark matter is examined at low temperatures relevant to neutron star cores. We calculate the equation of state and the composition of matter…

Nuclear Theory · Physics 2008-11-26 Kei Iida , Katsuhiko Sato

The extended nonlinear model has been applied to construct neutron star matter equation of state. In the case of neutron star matter with non-zero strangeness the extension of the vector meson sector by the inclusion of nonlinear mixed…

Nuclear Theory · Physics 2009-08-03 Ilona Bednarek , Ryszard Manka

Neutron star tidal deformability extracted from gravitational wave data provides a novel probe to the interior neutron star structures and the associated nuclear equation of state (EOS). Instead of the popular composition of nucleons and…

Nuclear Theory · Physics 2021-09-27 W. Z. Shangguan , Z. Q. Huang , S. N. Wei , W. Z. Jiang

The properties of compact stars and their formation processes depend on many physical ingredients. The composition and the thermodynamics of the involved matter is one of them. We will investigate here uniform strongly interacting matter at…

Nuclear Theory · Physics 2016-04-20 M. Oertel , F. Gulminelli , C. Providencia , A. R. Raduta

The vacuum fluctuation (VF) effects on the properties of the hyperonic neutron star matter are investigated in the framework of the relativistic mean field (RMF) theory. The VF corrections result in the density dependence of in-medium…

High Energy Physics - Phenomenology · Physics 2009-10-29 M. -H. Weng , X. -H. Guo , B. Liu

For neutron stars with hyperon-mixed core, neutrino emissivity is studied under the equation of state, obtained by introducing repulsive three-body force universal for all baryons so as to assure the maximum mass compatible with the…

Nuclear Theory · Physics 2009-11-10 T. Takatsuka , R. Tamagaki

Viscosity plays a critical role in determining the stability of rotating neutron stars. We report the results of a calculation of the shear viscosity of $\beta$~-~stable matter, carried out using an effective interaction based on a…

Nuclear Theory · Physics 2009-12-02 Omar Benhar , Arianna Carbone