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Related papers: Gravity modes in rapidly rotating polytropic stars

200 papers

The post-bounce oscillations of newly-born relativistic stars are expected to lead to gravitational-wave emission through the excitation of nonradial oscillation modes. At the same time, the star is oscillating in its radial modes, with a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Andrea Passamonti , Nikolaos Stergioulas , Alessandro Nagar

We propose a methodological framework to perform forward asteroseismic modeling of stars with a convective core, based on gravity-mode oscillations. These probe the near-core region in the deep stellar interior. The modeling relies on a set…

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

We present the results of numerical time evolutions of the linearised perturbations of rapidly and rigidly rotating Newtonian polytropes while making the Cowling approximation. The evolution code runs stably for hundreds of stellar…

Astrophysics · Physics 2009-11-07 D. I. Jones , N. Andersson , N. Stergioulas

The r-mode instability in rotating relativistic stars has been shown recently to have important astrophysical implications (including the emission of detectable gravitational radiation, the explanation of the initial spins of young neutron…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Nikolaos Stergioulas , Jose A. Font

We present an asymptotic theory that describes regular frequency spacings of pressure modes in rapidly rotating stars. We use an asymptotic method based on an approximate solution of the pressure wave equation constructed from a stable…

Solar and Stellar Astrophysics · Physics 2012-09-27 Michael Pasek , François Lignières , Bertrand Georgeot , Daniel R. Reese

Two-imcompressible phase model of star is briefly revised. Effects of rotation and general relativity are considered.

Astrophysics · Physics 2007-05-23 Zakir F. Seidov

We explore the impact of modified gravity on B-modes, identifying two main separate effects: lensing and propagation of tensor modes. The location of the inflationary peak of the BB spectrum depends on the speed of gravitational waves; the…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-27 Luca Amendola , Guillermo Ballesteros , Valeria Pettorino

Gravitational waves from neutron star binary inspirals contain information on strongly-interacting matter in unexplored, extreme regimes. Extracting this requires robust theoretical models of the signatures of matter in the…

General Relativity and Quantum Cosmology · Physics 2021-08-18 Jan Steinhoff , Tanja Hinderer , Tim Dietrich , Francois Foucart

We study the fully non-adiabatic tidal response of a uniformly rotating unevolved 20 Msun star to the dominant l=m=2 component of the companion's perturbing potential. This is done numerically with a 2D implicit finite difference scheme. We…

Astrophysics · Physics 2015-06-24 G. J. Savonije , J. C. Papaloizou

In several classes of modified gravity theories, extra degrees of freedom are not completely screened in the interiors of stellar and substellar objects. In such theories, the hydrostatic equilibrium condition inside these objects is…

General Relativity and Quantum Cosmology · Physics 2023-10-27 Shaswata Chowdhury

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

Context. Slowly pulsating B (SPB) stars display multi-periodic variability in the gravito-inertial mode regime with indications of non-linear resonances between modes. Several have undergone asteroseismic modeling in the past few years to…

Solar and Stellar Astrophysics · Physics 2024-07-31 Jordan Van Beeck , Tim Van Hoolst , Conny Aerts , Jim Fuller

In the context of the determination of stellar properties using asteroseismology, we study the influence of rotation and convective-core overshooting on the properties of red-giant stars. We used models in order to investigate the effects…

Solar and Stellar Astrophysics · Physics 2015-12-14 Nadège Lagarde , Diego Bossini , Andrea Miglio , Mathieu Vrard , Benoit Mosser

In this work, we study the impact of anisotropy on slowly rotating neutron stars by extending the Hartle-Thorne formalism in general relativity to include anisotropy in pressure up to second order in the angular velocity. We assess the…

General Relativity and Quantum Cosmology · Physics 2024-10-10 L. M. Becerra , E. A. Becerra-Vergara , F. D. Lora-Clavijo

In {\gamma} Doradus stars, gravito-inertial modes in the radiative zone and inertial modes in the convective core can interact resonantly, which translates into the appearance of dip structures in the period spacing of modes. Those dips are…

Solar and Stellar Astrophysics · Physics 2024-09-18 Marion Galoy , François Lignières , Jérôme Ballot

We examine the inertial modes of vibration of a Maclaurin spheroid and determine how they are driven by an external tidal field, either Newtonian (gravitoelectric) or post-Newtonian (gravitomagnetic). The context and motivation for this…

General Relativity and Quantum Cosmology · Physics 2020-11-11 Eric Poisson , Cyann Buisson

The relation of period spacing ($\Delta P$) versus period ($P$) of dipole prograde g modes is known to be useful to measure rotation rates in the g-mode cavity of rapidly rotating $\gamma$ Dor and slowly pulsating B (SPB) stars. In a…

Solar and Stellar Astrophysics · Physics 2021-03-03 Hideyuki Saio , Masao Takata , Umin Lee , Gang Li , Timothy Van Reeth

The present paper is devoted to a study of the equilibrium configurations of slowly rotating anisotropic stars in the framework of general relativity. For that purpose, we provide the equations of structure where the rotation is treated to…

General Relativity and Quantum Cosmology · Physics 2024-07-23 Philip Beltracchi , Camilo Posada

We consider the slowly rotating relativistic stars with a uniform angular velocity in the scalar-tensor gravity, and examine the rotational effect around such compact objects. For this purpose, we derive a 2nd order differential equation…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Hajime Sotani