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Related papers: Instability windows of relativistic r-modes

200 papers

In the present paper we examine gravitational wave asteroseismology relations for f-modes of rapidly rotating neutron stars. An approach different to the previous studies is employed - first, the moment of inertia is used instead of the…

Solar and Stellar Astrophysics · Physics 2015-12-09 Daniela D. Doneva , Kostas D. Kokkotas

We investigate the damping of neutron star r-modes due to the presence of a viscous boundary (Ekman) layer at the interface between the crust and the core. Our study is motivated by the possibility that the gravitational-wave driven…

Astrophysics · Physics 2009-11-11 Kostas Glampedakis , Nils Andersson

We investigate the effect of antikaon condensed matter on bulk viscosity in rotating neutron stars. We use relativistic field theoretical models to construct the equation of state of neutron stars with the condensate, where the phase…

Astrophysics · Physics 2007-12-31 Debarati Chatterjee , Debades Bandyopadhyay

A phase transition occurring in the inner core of a neutron star could be associated to a density discontinuity that would affect the frequency spectrum of the non-radial oscillation modes in two ways. Firstly, it would produce a softening…

Astrophysics · Physics 2009-11-07 G. Miniutti , J. A. Pons , E. Berti , L. Gualtieri , V. Ferrari

We investigate f-mode oscillations of static anisotropic stable neutron stars within the framework of full general relativity. We present equations governing unperturbed stellar structures and oscillations with an ansatz to account for the…

General Relativity and Quantum Cosmology · Physics 2025-02-25 Sushovan Mondal , Manjari Bagchi

We investigate the modal properties of the $r$-modes of rotating neutron stars with the core filled with neutron and proton superfluids, taking account of entrainment effects between the superfluids. The stability of the $r$-modes against…

Astrophysics · Physics 2008-11-26 Umin Lee , Shijun Yoshida

We investigate the role of r-mode oscillations in pulsar spin-down and their implications for gravitational wave emission and pulsar timing analysis. Using a non-linear differential framework that includes r-mode contributions, we derive…

High Energy Astrophysical Phenomena · Physics 2025-09-15 Xiyuan Li , Shahram Abbassi , Varenya Upadhyaya , Xiyang Zhang , S. R. Valluri

At second order in perturbation theory, the $r$-modes of uniformly rotating stars include an axisymmetric part that can be identified with differential rotation of the background star. If one does not include radiation-reaction, the…

High Energy Astrophysical Phenomena · Physics 2018-03-07 John L. Friedman , Lee Lindblom , Keith H. Lockitch

We constrain the fundamental-mode ($f$-mode) oscillation frequencies of nonrotating neutron stars using a phenomenological Gaussian process model for the unknown dense-matter equation of state conditioned on a suite of gravitational-wave,…

High Energy Astrophysical Phenomena · Physics 2026-01-01 Sailesh Ranjan Mohanty , Utkarsh Mali , H. C. Das , Bharat Kumar , Philippe Landry

We use a simple physical model to study the nonlinear behaviour of the r-mode instability. We assume that r-modes (Rossby waves) are excited in a thin spherical shell of rotating incompressible fluid. For this case, exact Rossby wave…

Astrophysics · Physics 2016-08-30 Yuri Levin , Greg Ushomirsky

We investigate inertial mode oscillations of slowly and uniformly rotating, isentropic, Newtonian stars. Inertial mode oscillations are induced by the Coriolis force due to the star's rotation, and their characteristic frequencies are…

Astrophysics · Physics 2016-08-30 Shijun Yoshida , Umin Lee

The spin rate \Omega of neutron stars at a given temperature T is constrained by the interplay between gravitational-radiation instabilities and viscous damping. Navier-Stokes theory has been used to calculate the viscous damping timescales…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Vahid Rezania , Roy Maartens

The nucleon-nucleon correlation between nucleons leads to the Fermi surface depletion measured by a $Z$-factor in momentum distribution of dense nuclear matter. The roles of the Fermi surface depletion effect ($Z$-factor effect) and its…

Nuclear Theory · Physics 2021-01-19 J. M. Dong

A comprehensive investigation of nonradial oscillations in neutron star (NS) admixed with gravitationally bounded dark matter (DM) is carried out within the framework of full general relativity. The relativistic mean field (RMF) formalism…

Nuclear Theory · Physics 2025-11-05 Pinku Routaray

The gravitational-wave and accretion driven evolution of neutron stars in low mass X-ray binaries and similar systems is analyzed, while the amplitude of the radiating perturbation (here assumed to be an r-mode) remains small. If most of…

Astrophysics · Physics 2009-11-06 Robert V. Wagoner , Joseph F. Hennawi , Jingsong Liu

Axial oscillations relevant to the r-mode instability are studied with slow rotation formalism in general relativity. The approximate equation governing the oscillations is derived with second-order rotational corrections. The equation…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Yasufumi Kojima , Masayasu Hosonuma

We analyze the stability of g-modes in variable white dwarfs with hydrogen envelopes. In these stars, the radiative layer contributes to mode damping because its opacity decreases upon compression and the amplitude of the Lagrangian…

Astrophysics · Physics 2009-10-08 Peter Goldreich , Yanqin Wu

We examine pulsational stability of low $m$ $r$ modes in SPB stars by calculating fully nonadiabatic oscillations of uniformly rotating stars, where $m$ is an integer representing the azimuthal wave number around the rotation axis. $R$…

Astrophysics · Physics 2009-11-13 Umin Lee

This article provides an overview of stellar instabilities as sources of gravitational waves. The aim is to put recent work on secular and dynamical instabilities in compact stars in context, and to summarize the current thinking about the…

Astrophysics · Physics 2017-08-23 N. Andersson

We analyze the viscous damping of r-mode oscillations of compact stars, taking into account non-linear viscous effects in the large-amplitude regime. The qualitatively different cases of hadronic stars, strange quark stars, and hybrid stars…

High Energy Astrophysical Phenomena · Physics 2013-05-30 Mark G. Alford , Simin Mahmoodifar , Kai Schwenzer