English
Related papers

Related papers: Stability of g-modes in rotating B-type stars

200 papers

In rapidly rotating stars Coriolis forces and centrifugal deformations modify the properties of oscillations; the Coriolis force is important for low-frequency modes, while the centrifugal deformation affects mainly p-modes. Here, we…

Solar and Stellar Astrophysics · Physics 2015-06-12 Hideyuki Saio

Several classes of stars (most notably O and B main-sequence stars, as well as accreting white dwarfs and neutron stars) rotate quite rapidly, at spin frequencies greater than the typical g-mode frequencies. We discuss how rapid rotation…

Astrophysics · Physics 2009-10-30 Greg Ushomirsky , Lars Bildsten

This paper explores the effect of rotation on the kappa-mechanism instability of slowly pulsating B stars. A new nonadiabatic code, that adopts the so-called `traditional approximation' to treat the Coriolis force, is used to investigate…

Astrophysics · Physics 2011-05-12 R. H. D. Townsend

This paper studies the oscillatory stability of uniformly rotating main-sequence stars of mass 3-8 M_sun by solving the linearized non-adiabatic, non-radial oscillation equations with a forcing term and searching for resonant response to a…

Astrophysics · Physics 2009-11-11 G. J. Savonije

We focus on the influence of the Coriolis acceleration on the stochastic excitation of oscillation modes in convective regions of rotating stars. Our aim is to estimate the asymmetry between excitation rates of prograde and retrograde…

Solar and Stellar Astrophysics · Physics 2015-05-14 K. Belkacem , S. Mathis , M. J. Goupil , R. Samadi

We discuss low-frequency g modes excited by resonant couplings with weakly unstable oscillatory convective modes in the rotating convective core in early-type main-sequence stars. Our non-adiabatic pulsation analyses including the effect of…

Solar and Stellar Astrophysics · Physics 2020-08-12 Umin Lee , Hideyuki Saio

Strong magnetic fields are expected to significantly modify the pulsation frequencies of waves propagating in the cores of red giants or in the radiative envelopes of intermediate- and high-mass main-sequence stars. We calculate the g-mode…

Solar and Stellar Astrophysics · Physics 2024-09-24 Nicholas Z. Rui , J. M. Joel Ong , Stéphane Mathis

We use the traditional approximation to describe oscillations with frequencies comparable to the angular rotation rate. Validity of this approximation in application to main-sequence B stars is discussed. Numerical results regarding mode…

Astrophysics · Physics 2008-11-26 W. A. Dziembowski , J. Daszynska-Daszkiewicz , A. A. Pamyatnykh

We study how rotation affects observable amplitudes of high-order g- and mixed r/g-modes and examine prospects for their detection and identification. Our formalism, which is described in some detail, relies on a nonadiabatic generalization…

Astrophysics · Physics 2007-05-23 J. Daszynska-Daszkiewicz , W. A. Dziembowski , A. A. Pamyatnykh

The first numerical study of axial (toroidal) pulsation modes of a slowly rotating relativistic star is presented. The calculation includes terms of first order in $\epsilon \equiv \Omega \sqrt{R^3/M}<<1$ ($R$ is the radius, $M$ is the mass…

General Relativity and Quantum Cosmology · Physics 2009-07-09 Nils Andersson

We investigate the properties of r-mode and inertial mode of slowly rotating, non-isentropic, Newtonian stars, by taking account of the effects of the Coriolis force and the centrifugal force. For the non-isentropic models we consider only…

Astrophysics · Physics 2010-11-19 Shijun Yoshida , Umin Lee

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

We determine instability domains on the Hertzsprung-Russel diagram for rotating main sequence stars with masses 2-20 $\mathrm M_\odot$. The effects of the Coriolis force are treated in the framework of the traditional approximation.…

Solar and Stellar Astrophysics · Physics 2017-05-31 Wojciech Szewczuk , Jadwiga Daszyńska-Daszkiewicz

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

We investigate the properties of relativistic $r$-modes of slowly rotating neutron stars by using a relativistic version of the Cowling approximation. In our formalism, we take into account the influence of the Coriolis like force on the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Shijun Yoshida , Umin Lee

We suggest that high-order g modes can be used as a probe of the internal magnetic field of SPB (slowly pulsating B) stars. The idea is based on earlier work by the authors which analytically investigated the effect of a vertical magnetic…

Astrophysics · Physics 2009-11-11 S. S. Hasan , J. -P. Zahn , J. Christensen-Dalsgaard

We discuss how the p- and g-mode frequencies calculated for rotating stars are affected by the way of including the centrifugal deformations. We find that p-mode frequencies are sensitive to the accuracy in treating the centrifugal…

Solar and Stellar Astrophysics · Physics 2011-09-13 Hideyuki Saio , Robert G. Deupree

We use time-evolutions of the linear perturbation equations to study the oscillations of rapidly rotating neutrons stars. Our models account for the buoyancy due to composition gradients and we study, for the first time, the nature of the…

Astrophysics · Physics 2009-11-13 A. Passamonti , B. Haskell , N. Andersson , D. I. Jones , I. Hawke

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 find that low-degree low-order g-modes become unstable in metal-poor low-mass stars due to the $\varepsilon$-mechanism of the pp-chain. Since the outer convection zone of these stars is limited only to the very outer layers, the…

Solar and Stellar Astrophysics · Physics 2015-06-04 Takafumi Sonoi , Hiromoto Shibahashi
‹ Prev 1 2 3 10 Next ›