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Related papers: Bulk viscosity in a neutron star mantle

200 papers

We derive analytic approximations of neutrino luminosities and heat capacities of neutron stars with nucleon cores valid for a wide class of equations of state of dense nucleon matter. The neutrino luminosities are approximated for the…

High Energy Astrophysical Phenomena · Physics 2016-12-15 D. D. Ofengeim , M. Fortin , P. Haensel , D. G. Yakovlev , J. L. Zdunik

We investigate the hyperon bulk viscosity due to the non-leptonic process $n + p \rightleftharpoons p + \Lambda $ in $K^-$ condensed matter and its effect on the r-mode instability in neutron stars. We find that the hyperon bulk viscosity…

Astrophysics · Physics 2011-02-11 Debarati Chatterjee , Debades Bandyopadhyay

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

We use the field theoretical model to perform relativistic calculations of neutrino energy losses caused by the direct Urca processes on nucleons in the degenerate baryon matter. By our analysis, in a free nucleon gas under beta…

High Energy Physics - Phenomenology · Physics 2017-08-23 L. B. Leinson

A hypothetical time-variation of the gravitational constant $G$ would cause neutron star matter to depart from beta equilibrium, due to the changing hydrostatic equilibrium. This forces non-equilibrium beta processes to occur, which release…

Astrophysics · Physics 2009-11-11 Paula Jofre , Andreas Reisenegger , Rodrigo Fernandez

We demonstrate that there exists a new mechanism for dissipating the energy of stellar oscillations. For neutron stars, in particular, we show that the mechanical energy of density perturbations is not only dissipated to heat via bulk…

Solar and Stellar Astrophysics · Physics 2010-06-24 Basil A. Sa'd , Jürgen Schaffner-Bielich

We apply our recently suggested statistical approach to thermal evolution of isolated neutron stars and accreting quasistationary neutron stars in X-ray transients for constraining the position and relative broadening alpha of the direct…

Solar and Stellar Astrophysics · Physics 2015-07-19 M. V. Beznogov , D. G. Yakovlev

We show that the neutron star in the transient system MXB~1659-29 has a core neutrino luminosity that substantially exceeds that of the modified Urca reactions (i.e., $n+n\to n+p+e^{-}+\bar{\nu}_{e}$ and inverse) and is consistent with the…

High Energy Astrophysical Phenomena · Physics 2018-05-09 Edward F. Brown , Andrew Cumming , Farrukh J. Fattoyev , C. J. Horowitz , Dany Page , Sanjay Reddy

We have investigated the crustal properties of neutron stars without fallback accretion. We have calculated the chemical evolution of the neutron star crust in three different cases (a modified Urca process without the thermal influence of…

Solar and Stellar Astrophysics · Physics 2015-05-13 Kelsey Hoffman , Jeremy Heyl

Magnetars are a subclass of neutron stars whose intense soft-gamma-ray bursts and quiescent X-ray emission are believed to be powered by the decay of a strong internal magnetic field. We reanalyze neutrino emission in such stars in the…

Astrophysics · Physics 2009-11-11 Mario Riquelme , Andreas Reisenegger , Olivier Espinosa , Claudio Dib

The direct Urca (dUrca) process is a key mechanism driving rapid neutrino cooling in neutron stars, with its baryon density activation threshold determined by the microscopic model for nuclear matter. Understanding how nuclear interactions…

Nuclear Theory · Physics 2025-11-26 Luigi Scurto , Helena Pais , Marco Antonelli , Francesca Gulminelli

Neutron stars are the densest objects in the Universe. They have microscopically homogeneous core and heterogeneous crust. In particular, there may be a specific layer inside neutron stars, the mantle, which consists of substantially…

High Energy Astrophysical Phenomena · Physics 2023-05-08 Nikita A. Zemlyakov , Andrey I. Chugunov

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

The production of light nuclei and hypernuclei together with heavy baryons, both hyperons and $\Delta$-baryons, in low density matter as found in stellar environments such as supernova or binary mergers is studied within relativistic…

Nuclear Theory · Physics 2022-06-29 Tiago Custódio , Helena Pais , Constança Providência

The role of direct URCA reactions in damping of the gravitational radiation driven instability is discussed. The temperature at which bulk viscosity suppresses completely this instability is calculated. The results are obtained analytically…

Astrophysics · Physics 2011-05-23 J. L. Zdunik

The results of recent multi-dimensional simulations of type-II supernovae are reviewed. They show that convective instabilities in the collapsed stellar core might play an important role already during the first second after the formation…

Astrophysics · Physics 2007-05-23 H. -Thomas Janka

We study the effects of an elastic crust on the oscillation spectrum of superfluid neutron stars. Within the two fluid formalism, we consider Newtonian stellar models that include the relevant constituents of a mature neutron stars. The…

Solar and Stellar Astrophysics · Physics 2015-05-28 A. Passamonti , N. Andersson

Oscillation modes of neutron stars, a key target for third-generation gravitational wave detectors, encode key information about their constituent nuclear matter. In this work, we study the effect of viscosity on oscillations of cold,…

General Relativity and Quantum Cosmology · Physics 2026-03-26 Lennox S. Keeble , Jaime Redondo-Yuste

In order to extract the precise physical information encoded in the gravitational and electromagnetic signals from powerful neutron-star merger events, we need to include as much of the relevant physics as possible in our numerical…

High Energy Astrophysical Phenomena · Physics 2022-05-19 T. Celora , I. Hawke , P. C. Hammond , N. Andersson , G. L. Comer

Thermal evolution of neutron stars is known to depend on the properties of superdense matter in neutron star cores. We suggest a statistical analysis of isolated cooling middle-aged neutron stars and old transiently accreting…

Solar and Stellar Astrophysics · Physics 2015-07-16 M. V. Beznogov , D. G. Yakovlev