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Related papers: Boundary layer on the surface of a neutron star

200 papers

X-ray spectra of quiescent low-mass X-ray binaries containing neutron stars can be fit with atmosphere models to constrain the mass and the radius. Mass-radius constraints can be used to place limits on the equation of state of dense…

High Energy Astrophysical Phenomena · Physics 2018-03-21 A. W. Shaw , C. O. Heinke , A. W. Steiner , S. Campana , H. N. Cohn , W. C. G. Ho , P. M. Lugger , M. Servillat

The transition density $n_t$ and pressure $P_t$ at the inner edge between the liquid core and the solid crust of a neutron star are analyzed using the thermodynamical method and the framework of relativistic nuclear energy density…

Nuclear Theory · Physics 2014-11-20 Ch. C. Moustakidis , T. Niksic , G. A. Lalazissis , D. Vretenar , P. Ring

We model the X-rays reprocessed by an accretion disk in a fiducial low-mass X-ray binary system with a neutron star primary. An atmosphere, or the intermediate region between the optically thick disk and a Compton-temperature corona, is…

Astrophysics · Physics 2009-11-06 M. A. Jimenez-Garate , J. C. Raymond , D. A. Liedahl , C. J. Hailey

We analyze the effect of the quadrupole component in the mass distribution of a rapidly rotating neutron star on energy release in the boundary layer on the surface of the accreting star and in the accretion disk in the cases where the…

Astrophysics · Physics 2007-05-23 N. R. Sibgatullin , R. A. Sunyaev

When a rotating neutron star loses angular momentum, the reduction of the centrifugal force makes it contract. This perturbs each fluid element, raising the local pressure and originating deviations from beta equilibrium, inducing reactions…

High Energy Astrophysical Phenomena · Physics 2015-05-18 Nicolás González-Jiménez , Cristóbal Petrovich , Andreas Reisenegger

I review attempts made to determine the properties of neutron stars. I focus on constraints on the maximum mass that a neutron star can have, and on attempts to measure neutron-star radii. So far, there appears to be only one neutron star…

Astrophysics · Physics 2017-08-23 M. H. van Kerkwijk

Precise and reliable measurements of the masses and radii of neutron stars with a variety of masses would provide valuable guidance for improving models of the properties of cold matter with densities above the saturation density of nuclear…

High Energy Astrophysical Phenomena · Physics 2016-04-20 M. Coleman Miller , Frederick K. Lamb

It was pointed out by Paczynski (1987) that the X-ray luminosity of accreting neutron stars is very sensitive to the physical properties of the accretion flow close to the innermost stable circular orbit. The X-ray radiation is dominated by…

Astrophysics · Physics 2009-11-13 Jiri Horak

We study the main astrophysical properties of differentially rotating neutron stars described as stationary and axisymmetric configurations of a moderately stiff $\Gamma=2$ polytropic fluid. The high level of accuracy and of stability of…

High Energy Astrophysical Phenomena · Physics 2017-03-08 Dorota Gondek-Rosinska , Izabela Kowalska , Loic Villain , Marcus Ansorg , Marcin Kucaba

The outermost layers of some neutron stars are likely to be dominated by hydrogen, as a result of fast gravitational settling of heavier elements. These layers directly mediate thermal radiation from the stars, and determine the…

Astrophysics · Physics 2009-10-30 Dong Lai , Edwin E. Salpeter

We describe a new method to incorporate thermonuclear heating in the envelope of accreting neutron star into long term simulations of their thermal evolution. We obtain boundary conditions for the heat exchange between the envelope and the…

High Energy Astrophysical Phenomena · Physics 2025-09-01 Martin Nava-Callejas , Dany Page , Yuri Cavecchi

The presence of a viscous boundary layer under the solid crust of a neutron star dramatically increases the viscous damping rate of the fluid r-modes. We improve previous estimates of this damping rate by including the effect of the…

Astrophysics · Physics 2009-10-31 Lee Lindblom , Benjamin J. Owen , Greg Ushomirsky

Currently used model of spherical accretion onto a magnetized rotating neutron star encounters major difficulties in explaining the entry rate of accreting material into the stellar field and spin evolution of long-period X-ray pulsars.…

High Energy Astrophysical Phenomena · Physics 2012-05-08 N. R. Ikhsanov , L. A. Pustil'nik , N. G. Beskrovnaya

Observations of thermal radiation from neutron stars allow one to measure the surface temperatures and confront them with cooling scenarios. Detection of gravitationally redshifted spectral lines can yield the mass-to-radius ratio. In the…

Astrophysics · Physics 2007-05-23 G. G. Pavlov , V. E. Zavlin

Recent observations of X-ray pulsars at low luminosities allow, for the first time, to compare theoretical models for the emission from highly magnetized neutron star atmospheres at low mass accretion rates ($\dot{M} \lesssim 10^{15}$ g…

Numerical simulations of radiative two-temperature hot accretion flows (HAFs) around Neutron stars (NSs) are performed. We assume that all of the energy carried by the HAF around a NS will be thermalized and radiated out at the surface of…

High Energy Astrophysical Phenomena · Physics 2020-02-26 De-Fu Bu , Erlin Qiao , Xiao-Hong Yang

This paper presents the results of a set of radiative hydrodynamic (RHD) simulations of convection in the near-surface regions of a rapidly rotating star. The simulations use microphysics consistent with stellar models, and include the…

Solar and Stellar Astrophysics · Physics 2020-06-10 Frank Robinson , Joel Tanner , Sarbani Basu

We use Smoothed Particle Hydrodynamics to study viscous accretion flows around a weakly magnetic neutron star. We show the formation of multiple ``boundary" layers in presence of both cooling and viscosity. We find that with the…

High Energy Astrophysical Phenomena · Physics 2019-06-26 Ayan Bhattacharjee , Sandip K. Chakrabarti

Models of thermal emission of neutron stars, presumably formed in their atmospheres, are needed to infer the surface temperatures, magnetic fields, chemical composition, and neutron star masses and radii from the observational data. This…

Astrophysics · Physics 2007-05-23 V. E. Zavlin , G. G. Pavlov

We use three-dimensional hydrodynamic numerical simulations to study phase transformations occurring in a clumpy interstellar gas exposed to time-dependent volumetric heating. To mimic conditions in the Galactic interstellar medium, we take…

Astrophysics · Physics 2009-11-07 Alexei G. Kritsuk , Michael L. Norman