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Related papers: The Parker Instability under a Linear Gravity

200 papers

Using an isothermal MHD code, we have performed three-dimensional, high-resolution simulations of the Parker instability. The initial equilibrium system is composed of exponentially-decreasing isothermal gas and magnetic field (along the…

Astrophysics · Physics 2009-10-30 Jongsoo Kim , S. S. Hong , Dongsu Ryu , T. W. Jones

A linear stability analysis has been performed onto a self-gravitating magnetized gas disk bounded by external pressure. The resulting dispersion relation is fully explained by three kinds of instability: a Parker-type instability driven by…

Astrophysics · Physics 2007-05-23 Sang Min Lee , Seung Soo Hong

A linear stability analysis of a multi-component and magnetized Galactic disk model is presented. The disk model uses the observed stratifications for the gas density and gravitational acceleration at the solar neighborhood and, in this…

Astrophysics · Physics 2009-10-31 Jongsoo Kim , Jose Franco , S. S. Hong , Alfredo Santillan , Marco A. Martos

To be a formation mechanism of such large-scale structures as giant molecular clouds (GMCs) and HI superclouds, the classical Parker instability driven by external gravity has to overcome three major obstacles: The convective motion…

Astrophysics · Physics 2015-06-24 Sang Min Lee , S. S. Hong

We present a detailed study of the growth of the Parker instability in a differentially rotating disk embedded in an azimuthal equilibrium magnetic field, such as the interstellar gas or an accretion disk. Basic properties of the…

Astrophysics · Physics 2007-05-23 T. Foglizzo , M. Tagger

We study the linear properties, nonlinear saturation and a steady, strongly nonlinear state of the Parker instability in galaxies. We consider magnetic buoyancy and its consequences with and without cosmic rays. Cosmic rays are described…

We describe the effects of both magnetic buoyancy and differential rotation on a disc of isothermal gas embedded in a purely azimuthal magnetic field, in order to study the evolution and interplay of Parker and shearing instabilities. Both…

Astrophysics · Physics 2016-08-30 Thierry Foglizzo , Michel Tagger

We present 2D, ideal-MHD numerical simulations of the Parker instability in a multi-component warm disk model. The calculations were done using two numerical codes with different algorithms, TVD and ZEUS-3D. The outcome of the numerical…

Astrophysics · Physics 2009-10-31 Alfredo Santillan , Jongsoo Kim , Jose Franco , Marco Martos , S. S. Hong , Dongsu Ryu

To examine how non-uniform nature of the Galactic gravity might affect length and time scales of the Parker instability, we took three models of gravity, uniform, linear and realistic ones. To make comparisons of the three gravity models on…

Astrophysics · Physics 2009-10-30 Jongsoo Kim , S. S. Hong

Parker instability arises from the presence of magnetic fields in a plasma in a gravitational field such as the interstellar medium (ISM), wherein the magnetic buoyant pressure expels the gas and causes the gas to move along the field…

High Energy Astrophysical Phenomena · Physics 2011-09-07 Chih-Yueh Wang , Ying-Yi Lo , Chung-Ming Ko

We study local radiation magnetohydrodynamic instabilities in static, optically thick, vertically stratified media with constant flux mean opacity. We include the effects of vertical gradients in a horizontal background magnetic field.…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Ted Tao , Omer Blaes

We investigate a perturbation problem for the three-dimensional compressible isentropic viscous magnetohydrodynamic system with zero resistivity in the presence of a modified gravitational force in a vertical strip domain in which the…

Analysis of PDEs · Mathematics 2019-02-15 Fei Jiang , Song Jiang

We present the results of linear analysis and two-dimensional local magnetohydrodynamic (MHD) simulations of the Parker instability, including the effects of cosmic rays (CRs), in magnetized gas disks (galactic disks). As an unperturbed…

Astrophysics · Physics 2009-11-10 Takuhito Kuwabara , Kenji Nakamura , C. M. Ko

We model the Parker instability in vertically stratified isothermal gas using non-ideal MHD three-dimensional simulations. Rotation, especially differential, more strongly and diversely affects the nonlinear state than the linear stage…

Astrophysics of Galaxies · Physics 2023-05-08 Devika Tharakkal , Anvar Shukurov , Frederick A. Gent , Graeme R. Sarson , Andrew Snodin

Parker instability leads to the formation of tangential discontinuities in a magnetic field and subsequent magnetic reconnection due to a numerical and/or an explicit resistivity. In this paper we investigate the role of the uniform,…

Astrophysics · Physics 2009-11-07 Grzegorz Kowal , Michal Hanasz , Katarzyna Otmianowska-Mazur

The effect of the magnetic skew on the Parker instability is investigated by means of the linear stability analysis for a gravitationally stratified gas layer permeated by a horizontal magnetic field. When the magnetic field is skewed…

Astrophysics · Physics 2009-10-22 T. Hanawa , R. Matsumoto , K. Shibata

The stability of nonaxisymmetric perturbations in differentially rotating astrophysical accretion disks is analyzed by fully incorporating the properties of shear flows. We verify the presence of discrete unstable eigenmodes with complex…

Astrophysics · Physics 2009-10-31 K. Noguchi , T. Tajima , R. Matsumoto

We use linear analysis to examine the effect of cosmic rays (CRs) on the Parker-Jeans instability of magnetized self-gravitating gaseous disks. We adopt a slab equilibrium model in which the gravity (including self-gravity) is perpendicular…

Astrophysics · Physics 2009-11-11 Takuhito Kuwabara , Chung-Ming Ko

We report the results of a local stability analysis for a magnetized, gravitationally stratified plasma containing cosmic rays. We account for cosmic-ray diffusion and thermal conduction parallel to the magnetic field and allow beta to take…

Astrophysics · Physics 2008-12-18 Timothy J. Dennis , Benjamin D. G. Chandran

We examine the evolution of the Parker instability in galactic disks using 3D numerical simulations. We consider a local Cartesian box section of a galactic disk, where gas, magnetic fields and cosmic rays are all initially in a…

Astrophysics of Galaxies · Physics 2015-12-24 Luiz Felippe S. Rodrigues , Graeme R. Sarson , Anvar Shukurov , Paul J. Bushby , Andrew Fletcher
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