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Related papers: r-modes in the Tolman VII solution

200 papers

We present a new numerical code to compute non-axisymmetric eigenmodes of rapidly rotating relativistic stars by adopting spatially conformally flat approximation of general relativity. The approximation suppresses the radiative degree of…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Shin'ichirou Yoshida

Relativistic Cowling approximation in which all metric perturbations are omitted is applied to non-axisymmetric infinitesimal oscillations of uniformly rotating general relativistic polytropes. Frequencies of lower order f-modes which are…

Astrophysics · Physics 2009-10-30 Shin'ichirou Yoshida , Yoshiharu Eriguchi

Accreting neutron stars (NS) can exhibit high frequency modulations in their lightcurves during thermonuclear X-ray bursts, known as burst oscillations. These frequencies can be offset from the NS spin frequency by several Hz (where known…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Frank R. N. Chambers , Anna L. Watts

The characteristic physical properties of rotating neutron stars under the r-mode oscillation are evaluated using the finite-range simple effective interaction. Emphasis is given on examining the influence of the stiffness of both the…

Nuclear Theory · Physics 2018-05-09 S. P. Pattnaik , T. R. Routray , X. Viñas , D. N. Basu , M. Centelles , K. Madhuri , B. Behera

We compute zero-frequency (neutral) quasi-normal f-modes of fully relativistic and rapidly rotating neutron stars, using several realistic equations of state (EOSs) for neutron star matter. The zero-frequency modes signal the onset of the…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Sharon M. Morsink , Nikolaos Stergioulas , Steve R. Blattnig

We study the radial pulsation frequencies of slowly rotating neutron stars in general relativistic formalism using realistic equations of state. It is found that the pulsation frequencies are always an increasing function of rotation rate.…

Astrophysics · Physics 2007-05-23 P. K. Sahu , A. R. Prasanna

A numerical study of nonlinear r-modes in isentropic, rapidly rotating relativistic stars, via 3-D general-relativistic hydrodynamical evolutions, is presented. On dynamical timescales, we find no evidence for strong coupling of r-modes to…

Astrophysics · Physics 2007-05-23 Jose A. Font , Nikolaos Stergioulas

We re-visit the calculation of mode oscillations in the ocean of a rotating neutron star, which may be excited during thermonuclear X-ray bursts. Our present theoretical understanding of ocean modes relies heavily on the traditional…

High Energy Astrophysical Phenomena · Physics 2023-05-23 F. Gittins , T. Celora , A. Beri , N. Andersson

We systematically examine the compactness of neutron stars as Tolman VII solutions in scalar-tensor theory of gravity. As a result, when the coupling constant is confined to values provided by astronomical observations we show that the…

General Relativity and Quantum Cosmology · Physics 2018-06-20 Hajime Sotani , Kostas D. Kokkotas

Nonradial oscillations of relativistic neutron stars with a solid crust are computed in the relativistic Cowling approximation, in which all metric perturbations are ignored. For the modal analysis, we employ three-component relativistic…

Astrophysics · Physics 2009-11-07 Shijun Yoshida , Umin Lee

We study the dynamical evolution of a large amplitude r-mode by numerical simulations. R-modes in neutron stars are unstable growing modes, driven by gravitational radiation reaction. In these simulations, r-modes of amplitude unity or…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Philip Gressman , Lap-Ming Lin , Wai-Mo Suen , N. Stergioulas , John L. Friedman

R-modes of a rotating neutron star are unstable because of the emission of gravitational radiation. We explore the saturation amplitudes of these modes determined by nonlinear mode-mode coupling. Modelling the star as incompressible allows…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Jeandrew Brink , Saul A. Teukolsky , Ira Wasserman

We propose a new method to study the quasi-normal modes of rotating relativistic stars. Oscillations are treated as perturbations in the frequency domain of the stationary, axisymmetric background describing a rotating star. The perturbed…

General Relativity and Quantum Cosmology · Physics 2008-11-26 V. Ferrari , L. Gualtieri , S. Marassi

We investigate non-axisymmetric low frequency modes of a rotating and magnetized neutron star, assuming that the star is threaded by a dipole magnetic field whose strength at the stellar surface, $B_0$, is less than $\sim 10^{12}$G, and…

Solar and Stellar Astrophysics · Physics 2015-05-14 Umin Lee

We describe how the nonlinear development of the R mode instability of neutron stars influences spin up to millisecond periods via accretion. Our arguments are based on nearly-resonant interactions of the R mode with pairs of "daughter…

Solar and Stellar Astrophysics · Physics 2013-10-30 Ruxandra Bondarescu , Ira Wasserman

The evolution of the r-mode instability is likely to be accompanied by secular kinematic effects which will produce differential rotation with large scale drifts of fluid elements, mostly in the azimuthal direction. As first discussed by…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Luciano Rezzolla , Frederick L. Lamb , Dragoljub Markovic , Stuart L. Shapiro

We derive the relativistic equations for stellar perturbations, including in a consistent way shear viscosity in the stress-energy tensor, and we numerically integrate our equations in the case of large viscosity. We consider the slow…

General Relativity and Quantum Cosmology · Physics 2010-11-11 L. Gualtieri , J. A. Pons , J. A. Miralles , V. Ferrari

We study non-linear axisymmetric pulsations of rotating relativistic stars using a general relativistic hydrodynamics code under the assumption of a conformal flatness. We compare our results to previous simulations where the spacetime…

Astrophysics · Physics 2009-11-11 Harald Dimmelmeier , Nikolaos Stergioulas , Jose A. Font

Several recent surprises appear dramatically to have improved the likelihood that the spin of rapidly rotating, newly formed neutron stars (and, possibly, of old stars spun up by accretion) is limited by a nonaxisymmetric instability driven…

General Relativity and Quantum Cosmology · Physics 2017-08-23 John L. Friedman , Keith H. Lockitch

We study the g-modes of fast rotating stratified neutron stars in the general relativistic Cowling approximation, where we neglect metric perturbations and where the background models take into account the buoyant force due to composition…

Solar and Stellar Astrophysics · Physics 2010-04-15 Erich Gaertig , Kostas D. Kokkotas