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Related papers: Double-Mode Stellar Pulsations

200 papers

The last decade lead to major progress in asteroseismology and stellar physics with the advent of space missions. Thanks to the richness and precision of current oscillation spectra, sophisticated seismic probing techniques allow us now to…

Solar and Stellar Astrophysics · Physics 2019-01-28 Marc-Antoine Dupret

We describe and discuss hydrodynamic simulations of the core helium flash using an initial model of a 1.25 M_sol star with a metallicity of 0.02 near at its peak. Past research concerned with the dynamics of the core helium flash is…

Solar and Stellar Astrophysics · Physics 2009-05-01 M. Mocak , E. Mueller , A. Weiss , K. Kifonidis

Emergent phenomena share the fascinating property of not being obvious consequences of the design of the system in which they appear. This characteristic is no less relevant when attempting to simulate such phenomena, given that the outcome…

Soft Condensed Matter · Physics 2014-11-26 D. C. Rapaport

Highly magnetized neutron stars are promising candidates to explain some of the most peculiar astronomical phenomena, for instance, fast radio bursts, gamma-ray bursts, and superluminous supernovae. Pulsations of these highly magnetized…

High Energy Astrophysical Phenomena · Physics 2023-03-13 Man Yin Leung , Anson Ka Long Yip , Patrick Chi-Kit Cheong , Tjonnie Guang Feng Li

Smoothed Particle Hydrodynamics is a multidimensional Lagrangian method of numerical hydrodynamics that has been used to tackle a wide variety of problems in astrophysics. Here we develop the basic equations of the SPH scheme, and we…

Astrophysics · Physics 2007-05-23 Frederic A. Rasio , James C. Lombardi

We have developed a multidimensional radiation hydrodynamics code to simulate the interaction of radial stellar pulsation and convection for full amplitude pulsating models. Convection is computed using large eddy simulations. Here we…

Solar and Stellar Astrophysics · Physics 2014-03-05 Christopher M. Geroux , Robert G. Deupree

Recently discrete dynamical models of walking droplet dynamics have allowed for fast numerical simulations of their horizontal chaotic motion and consequently the long-time statistical distribution of the droplet position. We develop a…

Dynamical Systems · Mathematics 2023-02-03 Gonzalo Ferrandez Quinto , Aminur Rahman

We develop a general formalism to treat, in general relativity, the nonradial oscillations of a superfluid neutron star about static (non-rotating) configurations. The matter content of these stars can, as a first approximation, be…

General Relativity and Quantum Cosmology · Physics 2009-11-07 N. Andersson , G. L. Comer , D. Langlois

A significant fraction of the envelope of low- and intermediate-mass stars is unstable to convection, leading to sub-surface turbulent motion. Here, we consider and include the effects of turbulence pressure in our stellar evolution…

Solar and Stellar Astrophysics · Physics 2015-11-06 Luca Grassitelli , Luca Fossati , Norbert Langer , Andrea Miglio , Alina Georgiana Istrate , Debashis Sanyal

We present a comprehensive study of MHD waves and instabilities in a weakly ionised system, e.g., an interstellar molecular cloud. We determine all the critical wavelengths of perturbations across which the sustainable wave modes can change…

Solar and Stellar Astrophysics · Physics 2011-04-01 Telemachos Ch. Mouschovias , Glenn E. Ciolek , S. A. Morton

We present results of a series of magnetohydrodynamic (MHD) and hydro- dynamic (HD) 2.5D simulations of the morphology of outflows driven by nested wide-angle winds - i.e. winds which eminate from a central star as well as from an orbiting…

Solar and Stellar Astrophysics · Physics 2014-11-20 Timothy J. Dennis , Adam Frank , Eric G. Blackman , Orsola DeMarco , Bruce Balick , Sorin Mitran

In this paper we consider a simple two-fluid model for pulsar glitches. We derive the basic equations that govern the spin evolution of the system from two-fluid hydrodynamics, accounting for the vortex mediated mutual friction force that…

High Energy Astrophysical Phenomena · Physics 2015-05-14 T. Sidery , A. Passamonti , N. Andersson

We present initial results of our study of numerical methods for modeling neutron star mergers (NSMs) with simulations that perform the full hydrodynamic evolution required to capture tidal effects, particularly in the last several orbits.…

Astrophysics · Physics 2007-05-23 Alan C. Calder , F. Douglas Swesty , Edward Y. M. Wang

In this article we present an analytical two-component model for pulsar rotational dynamics. Under the assumption of axial symmetry, implemented by a paraxial array of straight vortices that thread the entire neutron superfluid, we are able…

Solar and Stellar Astrophysics · Physics 2016-09-28 Marco Antonelli , Pierre Pizzochero

We consider the problem of incompressible, forced, nonhelical, homogeneous and isotropic MHD turbulence with no mean magnetic field and large magnetic Prandtl number. This type of MHD turbulence is the end state of the turbulent dynamo,…

We develop a numerical hydrodynamics code using a pseudo-Newtonian formulation that uses the weak field approximation for the geometry, and a generalized source term for the Poisson equation that takes into account relativistic effects. The…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Jinho Kim , Hee Il Kim , Matthew William Choptuik , Hyung Mok Lee

Global magnetohydrodynamic (MHD) instabilities are investigated in a computationally tractable two-dimensional model of the solar tachocline. The model's differential rotation yields stability in the absence of a magnetic field, but if a…

Plasma Physics · Physics 2019-02-19 Abigail Plummer , J. B. Marston , S. M. Tobias

We have obtained ultra-high quality spectra (R=180,000; S/N>300) with unprecedented wavelength coverage (4400 to 7400 A) for a number of stars covering most of the HR diagram in order to test the predictions of models of stellar surface…

Solar and Stellar Astrophysics · Physics 2009-09-01 I. Ramirez , C. Allende Prieto , D. L. Lambert , L. Koesterke , M. Asplund

Numerical simulations of magneto-convection have greatly expanded our understanding of stellar interiors and stellar magnetism. Recently, fully compressible hydrodynamical simulations of full-star models have demonstrated the feasibility of…

Solar and Stellar Astrophysics · Physics 2022-08-03 José R. Canivete Cuissa , Romain Teyssier

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