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Related papers: Instability windows of relativistic r-modes

200 papers

The impact of the combination of rotation and magnetic fields on oscillations of stellar fluids is still not well known theoretically. It mixes Alfv\'en and inertial waves. Neutron stars are a place where both effects may be at work. We…

High Energy Astrophysical Phenomena · Physics 2015-05-30 S. Abbassi , M. Rieutord , V. Rezania

We consider both mode calculations and time evolutions of axial r-modes for relativistic uniformly rotating non-barotropic neutron stars, using the slow-rotation formalism, in which rotational corrections are considered up to linear order…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Johannes Ruoff , Kostas D. Kokkotas

The only r-modes that exist in a globally barotropic, rotating, Newtonian star are the fundamental $l = |m|$ solutions, where $l$ and $m$ are the indices of the spherical harmonic $Y_l^m$ that describe the mode's angular dependence. This is…

General Relativity and Quantum Cosmology · Physics 2023-05-23 Fabian Gittins , Nils Andersson

The Rossby mode (r-mode) perturbations in pulsars as a steady gravitational wave (GW) sources have been explored. The time evolution and the intensity of the emitted GWs in terms of the strain tensor amplitude have been estimated with the…

Nuclear Theory · Physics 2023-05-01 Joydev Lahiri , D. N. Basu

I suggest a novel approach for deriving evolution equations for rapidly rotating relativistic stars affected by radiation-driven Chandrasekhar-Friedman-Schutz (CFS) instability. This approach is based on the multipolar expansion of…

High Energy Astrophysical Phenomena · Physics 2017-10-19 Andrey I. Chugunov

An inconsistency between the theoretical analysis and numerical calculations of the relativistic $r$-modes puzzles the neutron star community since the Kojima's finding of the continuous part in the $r$-mode oscillation spectrum in 1997. In…

High Energy Astrophysical Phenomena · Physics 2022-11-16 Kirill Y. Kraav , Mikhail E. Gusakov , Elena M. Kantor

The frequencies of r-mode oscillations of rotating neutron stars can be useful for guiding and interpreting gravitational wave and electromagnetic observations. The frequencies of slowly rotating, barotropic, and non-magnetic Newtonian…

General Relativity and Quantum Cosmology · Physics 2015-01-14 Ashikuzzaman Idrisy , Benjamin J. Owen , David I. Jones

We investigate the properties of $r$-mode oscillations of a slowly rotating neutron star with a solid crust, by taking account of the effects of the Coriolis force. For the modal analysis we employ three-component neutron star models that…

Astrophysics · Physics 2009-10-31 Shijun Yoshida , Umin Lee

Using a simple model of a neutron star with a perfectly rigid crust constructed and a set of crust and core equations of state that span the range of nuclear experimental uncertainty in the density dependence of the symmetry energy from 25…

Solar and Stellar Astrophysics · Physics 2015-05-30 De-Hua Wen , W. G. Newton , Bao-An Li

We study non-axisymmetric oscillations of rapidly and differentially rotating relativistic stars in the Cowling approximation. Our equilibrium models are sequences of relativistic polytropes, where the differential rotation is described by…

Solar and Stellar Astrophysics · Physics 2010-04-22 Christian Krüger , Erich Gaertig , Kostas D. Kokkotas

We discuss the role of differential rotation in the evolution of the l=2 r-mode instability of a newly born, hot, rapidly-rotating neutron star. It is shown that the amplitude of the r-mode saturates in a natural way at a value that depends…

Astrophysics · Physics 2017-08-23 Paulo M. Sá , Brigitte Tomé

We investigate the dynamics of r modes at amplitudes in the nonlinear regime for rapidly but uniformly rotating neutron stars with a polytropic equation of state. For this, we perform three-dimensional relativistic hydrodynamical…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Wolfgang Kastaun

We consider a rotating neutron star with the presence of hyperons in its core, using an equation of state in an effective chiral model within the relativistic mean field approximation. We calculate the hyperonic bulk viscosity coefficient…

High Energy Physics - Phenomenology · Physics 2014-11-20 T. K. Jha , H. Mishra , V. Sreekanth

We study the low T/W instability associated with the f-mode of differentially rotating stars. Our stellar models are described by a polytropic equation of state and the rotation profile is given by the standard j-constant law. The…

Solar and Stellar Astrophysics · Physics 2015-06-22 Andrea Passamonti , Nils Andersson

In the present paper we study the oscillations of fast rotating neutron stars with realistic equations of state (EoS) within the Cowling approximation. We derive improved empirical relations for gravitational wave asteroseismology with…

Solar and Stellar Astrophysics · Physics 2013-09-04 Daniela D. Doneva , Erich Gaertig , Kostas D. Kokkotas , Christian Krüger

Dwarf novae are a subset of cataclysmic variables that accrete material intermittently in short-duration outbursts with sometimes long quiescent intervals in between. During the quiescent state, the white dwarf (WD) photosphere may be…

Solar and Stellar Astrophysics · Physics 2025-12-25 Praphull Kumar , Dean M. Townsley

$r$-mode oscillations in rotating neutron stars are a source of continuous gravitational radiation. We investigate the excitation of $r$-modes by the mechanical impact on the neutron star surface of stochastically accreted clumps of matter,…

High Energy Astrophysical Phenomena · Physics 2025-02-20 Wenhao Dong , Andrew Melatos

We present a simple spin evolution model that predicts that rapidly rotating accreting neutron stars will mainly be confined to a narrow range of spin-frequencies; P= 1.5-5 ms. This is in agreement with current observations of both neutron…

Astrophysics · Physics 2009-10-31 N. Andersson , D. I. Jones , K. D. Kokkotas , N. Stergioulas

We constrain the parameters of neutron superfluidity in the cores of neutron stars making use of the recently proposed effect of resonance stabilization of $r$-modes. To this end, we, for the first time, calculate the finite-temperature…

High Energy Astrophysical Phenomena · Physics 2020-10-21 Elena M. Kantor , Mikhail E. Gusakov , Vasiliy A. Dommes

In coalescing neutron star binaries, r-modes in one of the stars can be resonantly excited by the gravitomagnetic tidal field of its companion. This post-Newtonian gravitomagnetic driving of these modes dominates over the Newtonian tidal…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Éanna É. Flanagan , Étienne Racine