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Related papers: Nonlinear r-modes in Rapidly Rotating Relativistic…

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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 axial mode oscillations are examined for relativistic rotating stars with uniform angular velocity. Using the slow rotation formalism and the Cowling approximation, we have derived the equations governing the r-mode oscillations up to…

Astrophysics · Physics 2015-06-24 Yasufumi Kojima , Masayasu Hosonuma

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

We revisit the problem of inertial r-modes in stratified stars, drawing on a more precise description of the composition stratification in a mature neutron star. The results highlight issues with the traditional approach to the problem,…

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

Superfluid hydrodynamics affects the spin-evolution of mature neutron stars, and may be key to explaining timing irregularities such as pulsar glitches. However, most models for this phenomenon exclude the global instability required to…

Solar and Stellar Astrophysics · Physics 2013-03-27 N. Andersson , K. Glampedakis , M. Hogg

The instability of r-mode oscillations in rapidly rotating neutron stars has attracted attention as a potential mechanism for producing high frequency, almost periodic gravitational waves. The analyses carried so far have shown the…

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

We present an analytic description of the $r$-mode instability in newly-born neutron stars, using the approximation of uniform density. Our computation is consistently accurate to second order in the angular velocity of the star. We obtain…

Astrophysics · Physics 2011-05-23 K. D. Kokkotas , N. Stergioulas

We investigate properties of $r$-mode instability in slowly rotating relativistic polytropes. Inside the star slow rotation and low frequency formalism that was mainly developed by Kojima is employed to study axial oscillations restored by…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Shijun Yoshida , Toshifumi Futamase

Rossby waves (or r-modes) on the surface of a neutron star have become a leading model for the oscillations observed during the tail of Type-I X-ray bursts. Their frequency evolution matches well with the observed frequency drifts of the…

Astrophysics · Physics 2009-11-10 Jeremy S. Heyl

Previously we found that large amplitude $r$-modes could decay catastrophically due to nonlinear hydrodynamic effects. In this paper we found the particular coupling mechanism responsible for this catastrophic decay, and identified the…

General Relativity and Quantum Cosmology · Physics 2009-07-30 Lap-Ming Lin , Wai-Mo Suen

Despite the recent excitement over the r-mode instability of rotating stars, these modes are not yet well-understood for stellar models appropriate to neutron stars - perfect fluid models in which both the equilibrium and perturbed…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Keith H. Lockitch

The rotation frequencies of young pulsars are systematically below their theoretical Kepler limit. R-modes have been suggested as a possible explanation for this observation. With the help of semi-analytic expressions that make it possible…

General Relativity and Quantum Cosmology · Physics 2018-07-25 Mark G. Alford , Kai Schwenzer

We study the dynamical evolution of the gravitational-wave driven instability of the f-mode in rapidly rotating relativistic stars. With an approach based on linear perturbation theory we describe the evolution of the mode amplitude and…

Solar and Stellar Astrophysics · Physics 2015-06-11 A. Passamonti , E. Gaertig , K. D. Kokkotas. D. Doneva

Pulsar spin frequencies and their time evolution are an important source of information on compact stars and their internal composition. Oscillations of the star can reduce the rotational energy via the emission of gravitational waves. In…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Mark Alford , Simin Mahmoodifar , Kai Schwenzer

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

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 have developed a new numerical scheme to solve r-mode oscillations of {\it rapidly rotating polytropic stars} in Newtonian gravity. In this scheme, Euler perturbations of the density, three components of the velocity are treated as four…

Astrophysics · Physics 2009-10-31 Shigeyuki Karino , Shin'ichirou Yoshida , Shijun Yoshida , Yoshiharu Eriguchi

In a second-order r-mode theory, S'a & Tom'e found that the r-mode oscillation in neutron stars (NSs) could induce stellar differential rotation, which leads to a saturation state of the oscillation spontaneously. Based on a consideration…

Solar and Stellar Astrophysics · Physics 2009-09-28 Yun-Wei Yu , Xiao-Feng Cao , Xiao-Ping Zheng

Axisymmetric pulsations of rotating neutron stars can be excited in several scenarios, such as core-collapse, crust and core-quakes and binary mergers and could become detectable either in gravitational waves or high-energy radiation. Here,…

Astrophysics · Physics 2009-10-31 Jose A. Font , Harald Dimmelmeier , Anshu Gupta , Nikolaos Stergioulas

In this work we study the r-mode instability windows and the gravitational wave signatures of neutron stars in the slow rotation approximation using the equation of state obtained from the density dependent M3Y effective interaction. We…

Nuclear Theory · Physics 2018-06-20 Somnath Mukhopadhyay , Joydev Lahiri , Debasis Atta , Kouser Imam , D. N. Basu