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Related papers: Nonlinear Pulsations of Convective Stellar Models

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The identification of pulsation modes in delta Scuti stars is mandatory to constrain the theoretical stellar models. The non-adiabatic observables used in the photometric identification methods depend, however,on convection modeling in the…

Astrophysics · Physics 2009-11-13 J. Montalban , M. -A. Dupret

We investigate the pulsation properties of stellar models representative of $\delta$ Scuti and $\gamma$ Doradus variables. We have calculated a grid of stellar models from 1.2 to 2.2 M$_{\odot}$, including the effects of both rotation and…

Solar and Stellar Astrophysics · Physics 2017-11-08 C. C. Lovekin , J. A. Guzik

"The purpose of numerical models is not numbers but insight." (Hamming) In the spirit of this adage, and of Don Cox's approach to scientific speaking, we discuss the questions that the latest generation of numerical models of the…

Astrophysics · Physics 2015-06-24 Mordecai-Mark Mac Low , Miguel A. de Avillez , Maarit J. Korpi

We present a finite difference code intended for computing linear, adiabatic, nonradial pulsations of spherical stars. This code is based on a general Newton - Raphson technique in order to handle the relaxation of the eigenvalue (square of…

Astrophysics · Physics 2009-11-06 A. H. Corsico , O. G. Benvenuto

We present numerical hydrodynamical evolutions of rapidly rotating relativistic stars, using an axisymmetric, nonlinear relativistic hydrodynamics code. We use four different high-resolution shock-capturing (HRSC) finite-difference schemes…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Jose A. Font , Nikolaos Stergioulas , Kostas D. Kokkotas

We show that equations governing pulsations of superfluid neutron stars can be splitted into two sets of weakly coupled equations, one describing the superfluid modes and another one -- the normal modes. The coupling parameter s is small,…

Solar and Stellar Astrophysics · Physics 2012-01-19 M. E. Gusakov , E. M. Kantor

Using time evolutions of the relevant linearised equations we study non-axisymmetric oscillations of rapidly rotating and superfluid neutron stars. We consider perturbations of Newtonian axisymmetric background configurations and account…

Astrophysics · Physics 2009-11-13 Andrea Passamonti , Brynmor Haskell , Nils Andersson

The existence of a superfluid core in the interior of a rotating neutron star may have an influence on its gravitational wave emission. In addition to the usually-assumed pure quadrupole radiation with the gravitational wave frequency at…

General Relativity and Quantum Cosmology · Physics 2014-05-06 M. Bejger , A. Królak

Nonlinear evolution of the gravitational radiation (GR) driven instability in the r-modes of neutron stars is studied by full numerical 3D hydrodynamical simulations. The growth of the r-mode instability is found to be limited by the…

Astrophysics · Physics 2009-11-07 Lee Lindblom , Joel E. Tohline , Michele Vallisneri

Stochatic excitation of stellar oscillations by turbulent convection is investigated and an expression for the power injected into the oscillations by the turbulent convection of the outer layers is derived which takes into account…

Astrophysics · Physics 2009-11-06 Reza Samadi , Marie-Jo Goupil

Oscillation modes of isolated compact stars can, in principle, be a fingerprint of the equation of state (EoS) of dense matter. We study the non-radial high-frequency l=2 spheroidal modes of neutron stars and strange quark stars, adopting a…

General Relativity and Quantum Cosmology · Physics 2017-12-20 C. Vasquez Flores , Zack B. Hall , Prashanth Jaikumar

We discuss the role of dynamical tidal effects for inspiralling neutron star binaries, focussing on features that may be considered "unmodelled" in gravitational-wave searches. In order to cover the range of possibilities, we consider i)…

High Energy Astrophysical Phenomena · Physics 2018-01-31 N. Andersson , W. C. G. Ho

Evolved cool stars of various masses are major cosmic engines, delivering substantial mechanical and radiative feedback to the interstellar medium through strong stellar winds and supernova ejecta. These stars play a pivotal role in…

Solar and Stellar Astrophysics · Physics 2024-02-02 Andrea Chiavassa , Kateryna Kravchenko , Jared A. Goldberg

Double-diffusive convection driven by both thermal and compositional buoyancy in a rotating cylindrical annulus with conical caps is considered with the aim to establish whether a small fraction of compositional buoyancy added to the…

Fluid Dynamics · Physics 2011-04-26 R. D. Simitev

We present a new survey of the radial oscillation modes of neutron stars. This study complements and corrects earlier studies of radial oscillations. We present an extensive list of frequencies for the most common equations of state and…

General Relativity and Quantum Cosmology · Physics 2011-05-23 Kostas. D. Kokkotas , Johannes Ruoff

Despite more and more observational data, stellar acoustic oscillation modes are not well understood as soon as rotation cannot be treated perturbatively. In a way similar to semiclassical theory in quantum physics, we use acoustic ray…

Solar and Stellar Astrophysics · Physics 2011-09-16 M. Pasek , B. Georgeot , F. Lignieres , D. R. Reese

We investigate simulated turbulent flow within thermally driven stellar convection zones. Different driving sources are studied, including cooling at the top of the convectively unstable region, as occurs in surface convection zones; and…

Solar and Stellar Astrophysics · Physics 2015-05-18 Casey Meakin , David Arnett

We describe an implicit 1--D adaptive mesh hydrodynamics code that is specially tailored for radial stellar pulsations. In the Lagrangean limit the code reduces to the well tested Fraley scheme. The code has the useful feature that…

Astrophysics · Physics 2009-10-30 J. Robert Buchler , Zoltan Kollath , Ariel Marom

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

Three-dimensional (3D) hydrodynamic simulations of shell oxygen burning (Meakin and Arnett 2007) exhibit bursty, recurrent fluctuations in turbulent kinetic energy. These are shown to be due to a global instability in the convective region,…

Solar and Stellar Astrophysics · Physics 2015-05-20 W. David Arnett , Casey Meakin