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Related papers: Bulk Viscosity in Neutron Stars from Hyperons

200 papers

In neutron stars, flavor-changing weak interactions determine the equilibrium fraction of protons over neutrons. In binary neutron-star mergers, violent changes in density modify this equilibrium value at timescales of milliseconds,…

Nuclear Theory · Physics 2024-02-13 Yumu Yang , Mauricio Hippert , Enrico Speranza , Jorge Noronha

Recent observations of neutron-star properties, in particular the recent detection of gravitational waves emitted from binary neutron stars, GW 170817, open the way to put strong constraints on nuclear interactions. In this paper, we review…

Nuclear Theory · Physics 2019-09-25 S. Gandolfi , J. Lippuner , A. W. Steiner , I. Tews , X. Du , M. Al-Mamun

We calculate the shear viscosity $\eta = \eta_{e\mu}+\eta_{n}$ in a neutron star core composed of nucleons, electrons and muons ($\eta_{e\mu}$ being the electron-muon viscosity, mediated by collisions of electrons and muons with charged…

Astrophysics · Physics 2009-02-20 P. S. Shternin , D. G. Yakovlev

We discuss different exotic phases and components of matter from the crust to the core of neutron stars based on theoretical models for equations of state relevant to core collapse supernova simulations and neutron star merger. Parameters…

High Energy Astrophysical Phenomena · Physics 2017-09-27 Debades Bandyopadhyay

The improved quark mass density- dependent model, which has been successfully used to describe the properties of both finite nuclei and bulk nuclear matter, is extended to include the strange quark. The parameters of the model are…

Nuclear Theory · Physics 2012-07-03 Chen Wu , Yu-Gang Ma , Wei-Liang Qian , Ru-Keng Su

We discuss the high-density nuclear equation of state within the Brueckner-Hartree-Fock approach. Particular attention is paid to the effects of nucleonic three-body forces, the presence of hyperons, and the joining with an eventual quark…

Astrophysics · Physics 2007-05-23 M. Baldo , G. F. Burgio , H. -J. Schulze

In this work we review the role of hyperons on the properties of neutron and proto-neutron stars. In particular, we revise the so-called "hyperon puzzle", go over some of the solutions proposed to tackle it, and discuss the implications…

Nuclear Theory · Physics 2016-03-23 Debarati Chatterjee , Isaac Vidana

We study the bulk viscosity in two (anti-spaghetti and Swiss cheese) phases of non- spherical nuclei in the mantle of an oscillating neutron star near the boundary with the stellar core. The bulk viscosity is produced by non-equilibrium…

High Energy Astrophysical Phenomena · Physics 2018-10-17 D. G. Yakovlev , M. E. Gusakov , P. Haensel

The current picture of the collapse and explosion of massive stars and the formation of neutron stars is reviewed. According to the favored scenario, however by no means proven and undisputed, neutrinos deposit the energy of the explosion…

Astrophysics · Physics 2010-11-19 H. -Th. Janka , K. Kifonidis , M. Rampp

We investigate the effect of the density-dependent proton and neutron gaps on vortex dynamics in neutron stars. We argue that the persistence of neutron star magnetic fields on timescales of $10^9$ y suggests a superconducting gap curve…

Nuclear Theory · Physics 2009-10-31 Stephen D. H. Hsu

Neutrino propagation in protoneutron stars requires the knowledge of the composition as well as the dynamical response function of dense hadronic matter. Matter at very high densities is probably composed of other particles than nucleons…

Nuclear Theory · Physics 2007-05-23 Arnau Rios , Artur Polls , Jerome Margueron

Strong interaction physics under extreme conditions of high temperature and/or density is of central interest in modern nuclear physics for experimentalists and theorists alike. In order to investigate such systems, model approaches that…

Solar and Stellar Astrophysics · Physics 2013-10-23 S. Schramm , V. Dexheimer , R. Negreiros , J. Steinheimer , T. Schürhoff

Neutrino emission caused by singlet Cooper pairing of baryons in neutron stars is recalculated by accurately taking into account for conservation of the vector weak currents. The neutrino emissivity via the vector weak currents is found to…

Astrophysics · Physics 2010-11-05 L. B. Leinson , A. Perez

We study the interaction of $\Lambda-$hyperon with proton and neutron inside a nucleus within the framework of relativistic mean field formalism. The single particle energy levels for some of the specific proton and neutron orbits are…

Nuclear Theory · Physics 2014-06-19 M. Ikram , S. K. Singh , S. K. Biswal , M. Bhuyan , S. K. Patra

We study the nuclear isentropic equation of state for a stellar matter composed of nucleons, hyperons, and $\Delta$-resonances. We investigate different snapshots of the evolution of a neutron star, from its birth as a lepton-rich…

Nuclear Theory · Physics 2023-09-19 Adamu Issifu , Kauan D. Marquez , Mateus R. Pelicer , Débora P. Menezes

We construct the equation of state of hypernuclear matter and study the structure of neutron stars employing a chiral hyperon-nucleon interaction of the J\"{u}lich--Bonn group tuned to femtoscopic $\Lambda p$ data of the ALICE…

Nuclear Theory · Physics 2025-03-18 I. Vidana , V. Mantovani Sarti , J. Haidenbauer , D. L. Mihaylov , L. Fabbietti

The early evolution of a protoneutron star depends both on the equation of state and neutrino interactions at high density. We identify the important sources of neutrino opacity and through model calculations show that in-medium effects…

Astrophysics · Physics 2007-05-23 S. Reddy , J. Pons , M. Prakash , J. M. Lattimer

We construct the equation of state (EOS) in a wide density range for neutron stars using the relativistic mean field theory. The properties of neutron star matter with both uniform and non-uniform distributions are studied consistently. The…

Nuclear Theory · Physics 2009-11-07 H. Shen

We investigate the role of higher order couplings, along with the condensation of antikaons ($K^-$ and $\bar K^0$), on the properties of neutron star (NS). We employ extended versions of the relativistic mean-field model, in which…

Nuclear Theory · Physics 2013-02-08 Neha Gupta , P. Arumugam

We present a neural network classification model for detecting the presence of hyperonic degrees of freedom in neutron stars. The models take radii and/or tidal deformabilities as input and give the probability for the presence of hyperons…

Nuclear Theory · Physics 2025-01-23 Valéria Carvalho , Márcio Ferreira , Constança Providência